Asp.net

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AbouttheTutorial
ASP.NET is a web application framework developed and marketed by Microsoft to
allow programmers to build dynamic web sites. It allows you to use a full-featured
programming language such as C# or VB.NET to build web applications easily.
This tutorial covers all the basic elements of ASP.NET that a beginner would
require to get started.
Audience
This tutorial is prepared for the beginners to help them understand basic ASP.NET
programming. After completing this tutorial, you will find yourself at a moderate
level of expertise in ASP.NET programming from where you can take yourself to
next levels.
Prerequisites
Before proceeding with this tutorial, you should have a basic understanding of
.NET programming language. As we are going to develop web-based applications
using ASP.NET web application framework, it will be good if you have an
understanding of other web technologies such as HTML, CSS, AJAX, etc.
Disclaimer&Copyright
 Copyright 2014 by Tutorials Point (I) Pvt. Ltd.
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manner without written consent of the publisher. We strive to update the contents
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or its contents including this tutorial. If you discover any errors on our website or
in this tutorial, please notify us at contact@tutorialspoint.com.

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Contents
About the Tutorial....................................................................................................................................i
Audience..................................................................................................................................................i
Prerequisites............................................................................................................................................i
Disclaimer & Copyright.............................................................................................................................i
Contents..................................................................................................................................................ii
1. INTRODUCTION...................................................................................................................1
What is ASP.NET?....................................................................................................................................1
ASP.NET Web Forms Model ....................................................................................................................1
The ASP.NET Component Model .............................................................................................................2
Components of .Net Framework 3.5........................................................................................................2
2. ENVIRONMENT SETUP.........................................................................................................5
The Visual Studio IDE ..............................................................................................................................5
Working with Views and Windows..........................................................................................................6
Adding Folders and Files to your wWebsite.............................................................................................6
Projects and Solutions.............................................................................................................................7
Building and Running a Project ...............................................................................................................7
3. LIFE CYCLE...........................................................................................................................8
ASP.NET Application Life Cycle................................................................................................................8
ASP.NET Page Life Cycle ..........................................................................................................................8
ASP.NET Page Life Cycle Events .............................................................................................................10
4. FIRST EXAMPLE..................................................................................................................12
Page Directives......................................................................................................................................12
Code Section .........................................................................................................................................12
Page Layout...........................................................................................................................................13
Using Visual Studio IDE .........................................................................................................................14

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5. EVENT HANDLING..............................................................................................................17
Event Arguments...................................................................................................................................17
Application and Session Events .............................................................................................................17
Page and Control Events........................................................................................................................17
Event Handling Using Controls ..............................................................................................................18
Default Events.......................................................................................................................................19
6. SERVER SIDE......................................................................................................................24
Server Object ........................................................................................................................................24
Request Object......................................................................................................................................26
Response Object ...................................................................................................................................28
7. SERVER CONTROLS............................................................................................................34
Properties of the Server Controls ..........................................................................................................35
Methods of the Server Controls ............................................................................................................38
8. HTML SERVER....................................................................................................................46
Advantages of using HTML Server Controls...........................................................................................46
9. CLIENT SIDE.......................................................................................................................52
Client Side Scripts..................................................................................................................................52
Client Side Source Code.........................................................................................................................53
10. BASIC CONTROLS...............................................................................................................56
Button Controls.....................................................................................................................................56
Text Boxes and Labels ...........................................................................................................................57
Check Boxes and Radio Buttons ............................................................................................................58
List Controls ..........................................................................................................................................58
The ListItemCollection Object ...............................................................................................................60
Radio Button list and Check Box List .....................................................................................................62
Bulleted lists and Numbered Lists .........................................................................................................63

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HyperLink Control .................................................................................................................................63
Image Control .......................................................................................................................................64
11. DIRECTIVES........................................................................................................................65
The Application Directive ......................................................................................................................65
The Assembly Directive .........................................................................................................................65
The Control Directive ............................................................................................................................66
The Implements Directive .....................................................................................................................67
The Import Directive .............................................................................................................................67
The Master Directive.............................................................................................................................67
The MasterType Directive .....................................................................................................................67
The OutputCache Directive ...................................................................................................................68
The Page Directive ................................................................................................................................68
The PreviousPageType Directive ...........................................................................................................69
The Reference Directive ........................................................................................................................69
The Register Directive ...........................................................................................................................70
12. MANAGING STATE.............................................................................................................71
View State.............................................................................................................................................71
Control State.........................................................................................................................................75
Session State.........................................................................................................................................75
Application State...................................................................................................................................81
13. VALIDATORS......................................................................................................................83
BaseValidator Class...............................................................................................................................83
RequiredFieldValidator Control.............................................................................................................84
RangeValidator Control.........................................................................................................................84
CompareValidator Control ....................................................................................................................85
RegularExpressionValidator ..................................................................................................................85
CustomValidator ...................................................................................................................................87

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ValidationSummary...............................................................................................................................88
Validation Groups .................................................................................................................................88
14. DATABASE ACCESS.............................................................................................................94
Retrieving and Displaying Data .............................................................................................................94
15. ADO.NET..........................................................................................................................101
The DataSet Class................................................................................................................................101
The DataTable Class ............................................................................................................................105
The DataRow Class..............................................................................................................................107
The DataAdapter Object......................................................................................................................108
The DataReader Object .......................................................................................................................108
DbCommand and DbConnection Objects ............................................................................................108
16. FILE UPLOADING..............................................................................................................113
17. AD ROTATORS .................................................................................................................117
The Advertisement File .......................................................................................................................117
Properties and Events of the AdRotator Class .....................................................................................120
Working with AdRotator Control.........................................................................................................121
18. CALENDARS.....................................................................................................................123
Properties and Events of the Calendar Control....................................................................................123
Working with the Calendar Control.....................................................................................................125
19. MULTI VIEWS...................................................................................................................130
Properties of View and MultiView Controls ........................................................................................130
20. PANEL CONTROLS............................................................................................................135
Working with the Panel Control ..........................................................................................................135
21. AJAX CONTROLS ..............................................................................................................142
The ScriptManager Control .................................................................................................................142
The UpdatePanel Control ....................................................................................................................143

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The UpdateProgress Control ...............................................................................................................147
The Timer Control ...............................................................................................................................148
22. DATA SOURCES................................................................................................................150
Data Source Views ..............................................................................................................................151
The SqlDataSource Control..................................................................................................................152
The ObjectDataSource Control............................................................................................................154
The AccessDataSource Control............................................................................................................157
23. DATA BINDING.................................................................................................................159
Simple Data Binding............................................................................................................................160
Declarative Data Binding.....................................................................................................................161
24. CUSTOM CONTROLS........................................................................................................170
User Controls ......................................................................................................................................170
Custom Controls..................................................................................................................................173
Working with Custom Controls ...........................................................................................................174
25. PERSONALIZATION ..........................................................................................................181
Understanding Profiles........................................................................................................................181
Attributes for the <add> Element........................................................................................................184
Anonymous Personalization................................................................................................................185
26. ERROR HANDLING ...........................................................................................................186
Tracing ................................................................................................................................................188
Error Handling.....................................................................................................................................192
27. DEBUGGING ....................................................................................................................194
Breakpoints.........................................................................................................................................194
The Debug Windows ...........................................................................................................................197
28. LINQ ................................................................................................................................199
LINQ Operators ...................................................................................................................................202

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29. SECURITY.........................................................................................................................207
Forms-Based Authentication...............................................................................................................207
IIS Authentication: SSL ........................................................................................................................215
30. DATA CACHING................................................................................................................217
What is Caching?.................................................................................................................................217
Caching in ASP.NET .............................................................................................................................217
Output Caching ...................................................................................................................................218
Data Caching .......................................................................................................................................220
Object Caching ....................................................................................................................................221
31. WEB SERVICES.................................................................................................................225
Creating a Web Service .......................................................................................................................225
Consuming the Web Service................................................................................................................230
Creating the Proxy...............................................................................................................................233
32. MULTITHREADING...........................................................................................................237
Creating Thread...................................................................................................................................237
Thread Life Cycle .................................................................................................................................237
Thread Priority ....................................................................................................................................238
Thread : Properties and Methods........................................................................................................238
33. CONFIGURATION.............................................................................................................246
Configuration Section Handler declarations ........................................................................................248
Application Settings ............................................................................................................................248
Connection Strings ..............................................................................................................................249
System.Web Element ..........................................................................................................................249
34. DEPLOYMENT..................................................................................................................257
XCOPY Deployment.............................................................................................................................257
Copying a Website ..............................................................................................................................257

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Creating a Setup Project......................................................................................................................258

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WhatisASP.NET?
ASP.NET is a web development platform, which provides a programming model, a
comprehensive software infrastructure and various services required to build up
robust web applications for PC as well as mobile devices.
ASP.NET works on top of the HTTP protocol, and uses the HTTP commands and
policies to set a browser-to-server bilateral communication and cooperation.
ASP.NET is a part of Microsoft .Net platform. ASP.NET applications are compiled
codes, written using the extensible and reusable components or objects present in
.Net framework. These codes can use the entire hierarchy of classes in .Net
framework.
ASP.NET application codes can be written in any of the following languages:
 C#
 Visual Basic.Net
 Jscript
 J#
ASP.NET is used to produce interactive, data-driven web applications over the
internet. It consists of a large number of controls such as text boxes, buttons, and
labels for assembling, configuring, and manipulating code to create HTML pages.
ASP.NETWebFormsModel
ASP.NET web forms extend the event-driven model of interaction to the web
applications. The browser submits a web form to the web server and the server
returns a full markup page or HTML page in response.
All client side user activities are forwarded to the server for stateful processing. The
server processes the output of the client actions and triggers the reactions.
Now, HTTP is a stateless protocol. ASP.NET framework helps in storing the
information regarding the state of the application, which consists of:
 Page state
 Session state
The page state is the state of the client, i.e., the content of various input fields in the
web form. The session state is the collective information obtained from various pages
the user visited and worked with, i.e., the overall session state. To clear the concept,
let us take an example of a shopping cart:
1. INTRODUCTION

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User adds items to a shopping cart. Items are selected from a page, say the items
page, and the total collected items and price are shown on a different page, say the
cart page. Only HTTP cannot keep track of all the information coming from various
pages. ASP.NET session state and server side infrastructure keeps track of the
information collected globally over a session.
ASP.NET runtime carries the page state to and from the server across page requests
while generating ASP.NET runtime codes, and incorporates the state of the server
side components in hidden fields.
This way, the server becomes aware of the overall application state and operates in
a two-tiered connected way.
TheASP.NETComponentModel
The ASP.NET component model provides various building blocks of ASP.NET pages.
Basically it is an object model, which describes:
 Server side counterparts of almost all HTML elements or tags such as <form>
and <input>.
 Server controls, which help in developing complex user-interface. For example,
the Calendar control or the Gridview control.
ASP.NET is a technology, which works on the .Net framework that contains all web-
related functionalities. The .Net framework is made of an object-oriented hierarchy.
An ASP.NET web application is made of pages. When a user requests an ASP.NET
page, the IIS delegates the processing of the page to the ASP.NET runtime system.
The ASP.NET runtime transforms the .aspx page into an instance of a class, which
inherits from the base class page of the .Net framework. Therefore, each ASP.NET
page is an object and all its components i.e., the server-side controls are also objects.
Componentsof.NetFramework3.5
Before going to the next session on Visual Studio.Net, let us go through the various
components of the .Net framework 3.5. The following table describes the components
of the .Net framework 3.5 and the job they perform:
Components and their Description
(1) Common Language Runtime or CLR
It performs memory management, exception handling, debugging, security
checking, thread execution, code execution, code safety, verification, and
compilation. The code that is directly managed by the CLR is called the managed
code. When the managed code is compiled, the compiler converts the source code

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into a CPU independent intermediate language (IL) code. A Just-In-Time (JIT)
compiler compiles the IL code into native code, which is CPU specific.
(2) .Net Framework Class Library
It contains a huge library of reusable types, classes, interfaces, structures, and
enumerated values, which are collectively called types.
(3) Common Language Specification
It contains the specifications for the .Net supported languages and implementation
of language integration.
(4) Common Type System
It provides guidelines for declaring, using, and managing types at runtime, and
cross-language communication.
(5) Metadata and Assemblies
Metadata is the binary information describing the program, which is either stored
in a portable executable file (PE) or in the memory. Assembly is a logical unit
consisting of the assembly manifest, type metadata, IL code, and a set of resources
like image files.
(6) Windows Forms
Windows forms contain the graphical representation of any window displayed in
the application.
(7) ASP.NET and ASP.NET AJAX
ASP.NET is the web development model and AJAX is an extension of ASP.NET for
developing and implementing AJAX functionality. ASP.NET AJAX contains the
components that allow the developer to update data on a website without a
complete reload of the page.
(8) ADO.NET
It is the technology used for working with data and databases. It provides access
to data sources like SQL server, OLE DB, XML etc. The ADO.NET allows connection
to data sources for retrieving, manipulating, and updating data.
(9) Windows Workflow Foundation (WF)
It helps in building workflow-based applications in Windows. It contains activities,
workflow runtime, workflow designer, and a rules engine.

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(10)Windows Presentation Foundation
It provides a separation between the user interface and the business logic. It helps
in developing visually stunning interfaces using documents, media, two and three
dimensional graphics, animations, and more.
(11) Windows Communication Foundation (WCF)
It is the technology used for building and executing connected systems.
(12) Windows CardSpace
It provides safety for accessing resources and sharing personal information on the
internet.
(13) LINQ
It imparts data querying capabilities to .Net languages using a syntax which is
similar to the tradition query language SQL.

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ASP.NET provides an abstraction layer on top of HTTP on which the web applications
are built. It provides high-level entities such as classes and components within an
object-oriented paradigm.
The key development tool for building ASP.NET applications and front ends is Visual
Studio. In this tutorial, we work with Visual Studio 2008.
Visual Studio is an integrated development environment for writing, compiling, and
debugging the code. It provides a complete set of development tools for building
ASP.NET web applications, web services, desktop applications, and mobile
applications.
TheVisualStudioIDE
The new project window allows choosing an application template from the available
templates.
When you start a new web site, ASP.NET provides the starting folders and files for
the site, including two files for the first web form of the site.
The file named Default.aspx contains the HTML and asp code that defines the form,
and the file named Default.aspx.cs (for C# coding) or the file named Default.aspx.vb
2. ENVIRONMENT SETUP

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(for VB coding) contains the code in the language you have chosen and this code is
responsible for the actions performed on a form.
The primary window in the Visual Studio IDE is the Web Forms Designer window.
Other supporting windows are the Toolbox, the Solution Explorer, and the Properties
window. You use the designer to design a web form, to add code to the control on
the form so that the form works according to your need, you use the code editor.
WorkingwithViewsandWindows
 You can work with windows in the following ways:
 To change the Web Forms Designer from one view to another, click on the
Design or source button.
 To close a window, click on the close button on the upper right corner and to
redisplay, select it from the View menu.
 To hide a window, click on its Auto Hide button. The window then changes into
a tab. To display again, click the Auto Hide button again.
 To change the size of a window, just drag it.
AddingFoldersandFilestoyourwWebsite
When a new web form is created, Visual Studio automatically generates the starting
HTML for the form and displays it in Source view of the web forms designer. The
Solution Explorer is used to add any other files, folders or any existing item on the
web site.
 To add a standard folder, right-click on the project or folder under which you
are going to add the folder in the Solution Explorer and choose New Folder.

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 To add an ASP.NET folder, right-click on the project in the Solution Explorer
and select the folder from the list.
 To add an existing item to the site, right-click on the project or folder under
which you are going to add the item in the Solution Explorer and select from
the dialog box.
ProjectsandSolutions
A typical ASP.NET application consists of many items: the web content files (.aspx),
source files (.cs files), assemblies (.dll and .exe files), data source files (.mdb files),
references, icons, user controls and miscellaneous other files and folders. All these
files that make up the website are contained in a Solution.
When a new website is created, VB2008 automatically creates the solution and
displays it in the solution explorer.
Solutions may contain one or more projects. A project contains content files, source
files, and other files like data sources and image files. Generally, the contents of a
project are compiled into an assembly as an executable file (.exe) or a dynamic link
library (.dll) file.
Typically a project contains the following content files:
 Page file (.aspx)
 User control (.ascx)
 Web service (.asmx)
 Master page (.master)
 Site map (.sitemap)
 Website configuration file (.config)
BuildingandRunningaProject
You can execute an application by:
 Selecting Start
 Selecting Start Without Debugging from the Debug menu,
 pressing F5
 Ctrl-F5
The program is built meaning, the .exe or the .dll files are generated by selecting a
command from the Build menu.

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ASP.NET life cycle specifies how:
 ASP.NET processes pages to produce dynamic output
 The application and its pages are instantiated and processed
 ASP.NET compiles the pages dynamically
ASP.NET life cycle could be divided into two groups:
 Application Life Cycle
 Page Life Cycle
ASP.NETApplicationLifeCycle
The application life cycle has the following stages:
1. User makes a request for accessing application resource, a page. Browser
sends this request to the web server.
2. A unified pipeline receives the first request and the following events take place:
i. An object of the class ApplicationManager is created.
ii. An object of the class HostingEnvironment is created to provide
information regarding the resources.
iii. Top level items in the application are compiled.
3. Response objects are created. The application objects such as HttpContext,
HttpRequest and HttpResponse are created and initialized.
4. An instance of the HttpApplication object is created and assigned to the
request.
5. The request is processed by the HttpApplication class. Different events are
raised by this class for processing the request.
ASP.NETPageLifeCycle
When a page is requested, it is loaded into the server memory, processed, and sent
to the browser. Then it is unloaded from the memory. At each of these steps, methods
and events are available, which could be overridden according to the need of the
application. In other words, you can write your own code to override the default code.
The Page class creates a hierarchical tree of all the controls on the page. All the
components on the page, except the directives, are part of this control tree. You can
see the control tree by adding trace= "true" to the page directive. We will cover page
directives and tracing under 'directives' and ‘event handling'.
The page life cycle phases are:
3. LIFE CYCLE

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 Initialization
 Instantiation of the controls on the page
 Restoration and maintenance of the state
 Execution of the event handler codes
 Page rendering
Understanding the page cycle helps in writing codes for making some specific thing
happen at any stage of the page life cycle. It also helps in writing custom controls
and initializing them at right time, populate their properties with view-state data and
run control behavior code.
Following are the different stages of an ASP.NET page:
Page request
When ASP.NET gets a page request, it decides whether to parse and compile the
page, or there would be a cached version of the page; accordingly the response is
sent.
Starting of page life cycle
At this stage, the Request and Response objects are set. If the request is an old
request or post back, the IsPostBack property of the page is set to true. The UICulture
property of the page is also set.
Page initialization
At this stage, the controls on the page are assigned unique ID by setting the UniqueID
property and the themes are applied. For a new request, postback data is loaded and
the control properties are restored to the view-state values.
Page load
At this stage, control properties are set using the view state and control state values.
Validation
Validate method of the validation control is called and on its successful execution,
the IsValid property of the page is set to true.
Postback event handling.
If the request is a postback (old request), the related event handler is invoked.
Page rendering
At this stage, view state for the page and all controls are saved. The page calls the
Render method for each control and the output of rendering is written to the
OutputStream class of the Response property of Page.

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Unload
The rendered page is sent to the client and page properties, such as Response and
Request, are unloaded and all cleanup done.
ASP.NETPageLifeCycleEvents
At each stage of the page life cycle, the page raises some events, which could be
coded. An event handler is basically a function or subroutine, bound to the event,
using declarative attributes such as Onclick or handle.
Following are the page life cycle events:
PreInit
PreInit is the first event in page life cycle. It checks the IsPostBack property and
determines whether the page is a postback. It sets the themes and master pages,
creates dynamic controls, and gets and sets profile property values. This event can
be handled by overloading the OnPreInit method or creating a Page_PreInit handler.
Init
Init event initializes the control property and the control tree is built. This event can
be handled by overloading the OnInit method or creating a Page_Init handler.
InitComplete
InitComplete event allows tracking of view state. All the controls turn on view-state
tracking.
LoadViewState
LoadViewState event allows loading view state information into the controls.
LoadPostData
During this phase, the contents of all the input fields are defined with the <form>
tag are processed.
PreLoad
PreLoad occurs before the post back data is loaded in the controls. This event can be
handled by overloading the OnPreLoad method or creating a Page_PreLoad handler.
Load

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The Load event is raised for the page first and then recursively for all child controls.
The controls in the control tree are created. This event can be handled by overloading
the OnLoad method or creating a Page_Load handler.
LoadComplete
The loading process is completed, control event handlers are run, and page validation
takes place. This event can be handled by overloading the OnLoadComplete method
or creating a Page_LoadComplete handler.
PreRender
The PreRender event occurs just before the output is rendered. By handling this
event, pages and controls can perform any updates before the output is rendered.
PreRenderComplete
As the PreRender event is recursively fired for all child controls, this event ensures
the completion of the pre-rendering phase.
SaveStateComplete
State of control on the page is saved. Personalization, control state and view state
information is saved. The HTML markup is generated. This stage can be handled by
overriding the Render method or creating a Page_Render handler.
UnLoad
The UnLoad phase is the last phase of the page life cycle. It raises the UnLoad event
for all controls recursively and lastly for the page itself. Final cleanup is done and all
resources and references, such as database connections, are freed. This event can
be handled by modifying the OnUnLoad method or creating a Page_UnLoad handler.

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An ASP.NET page is made up of a number of server controls along with HTML controls,
text, and images. Sensitive data from the page and the states of different controls
on the page are stored in hidden fields that form the context of that page request.
ASP.NET runtime controls the association between a page instance and its state. An
ASP.NET page is an object of the Page or inherited from it.
All the controls on the pages are also objects of the related control class inherited
from a parent Control class. When a page is run, an instance of the object page is
created along with all its content controls.
An ASP.NET page is also a server side file saved with the .aspx extension. It is
modular in nature and can be divided into the following core sections:
 Page Directives
 Code Section
 Page Layout
PageDirectives
The page directives set up the environment for the page to run. The @Page directive
defines page-specific attributes used by ASP.NET page parser and compiler. Page
directives specify how the page should be processed, and which assumptions need
to be taken about the page.
It allows importing namespaces, loading assemblies, and registering new controls
with custom tag names and namespace prefixes.
CodeSection
The code section provides the handlers for the page and control events along with
other functions required. We mentioned that, ASP.NET follows an object model. Now,
these objects raise events when some events take place on the user interface, like
a user clicks a button or moves the cursor. The kind of response these events need
to reciprocate is coded in the event handler functions. The event handlers are nothing
but functions bound to the controls.
The code section or the code behind file provides all these event handler routines,
and other functions used by the developer. The page code could be precompiled and
deployed in the form of a binary assembly.
4. FIRST EXAMPLE

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PageLayout
The page layout provides the interface of the page. It contains the server controls,
text, inline JavaScript, and HTML tags.
The following code snippet provides a sample ASP.NET page explaining Page
directives, code section and page layout written in C#:

<% @Page Language="C#" %>

<script runat="server">
private void convertoupper(object sender, EventArgs e)
{
string str = mytext.Value;
changed_text.InnerHtml = str.ToUpper();
}
</script>

<html>
<head> <title> Change to Upper Case </title> </head>
<body>
<h3> Conversion to Upper Case </h3>
<form runat="server">
<input runat="server" id="mytext" type="text" />
<input runat="server" id="button1" type="submit"
value="Enter..." OnServerClick="convertoupper"/>
<hr />
<h3> Results: </h3>
<span runat="server" id="changed_text" />

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</form>
</body>
</html>
Copy this file to the web server root directory. Generally it is c:inetputwwwroot.
Open the file from the browser to execute it and it generates the following result:
UsingVisualStudioIDE
Let us develop the same example using Visual Studio IDE. Instead of typing the code,
you can just drag the controls into the design view:
The content file is automatically developed. All you need to add is the Button1_Click
routine, which is as follows:
protected void Button1_Click(object sender, EventArgs e)
{
string buf = TextBox1.Text;
changed_text.InnerHtml = buf.ToUpper();
}

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The content file code is as given:
<%@ Page Language="C#" AutoEventWireup="true"
CodeBehind="Default.aspx.cs"
Inherits="firstexample._Default" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<asp:TextBox ID="TextBox1" runat="server" style="width:224px">
</asp:TextBox>
<br />
<br />
<asp:Button ID="Button1" runat="server" Text="Enter..."
style="width:85px" onclick="Button1_Click" />
<hr />
<h3> Results: </h3>
<span runat="server" id="changed_text" />
</div>
</form>
</body>
</html>

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Execute the example by right clicking on the design view and choosing 'View in
Browser' from the popup menu. This generates the following result:

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An event is an action or occurrence such as a mouse click, a key press, mouse
movements, or any system-generated notification. A process communicates through
events. For example, interrupts are system-generated events. When events occur,
the application should be able to respond to it and manage it.
Events in ASP.NET are raised at the client machine and handled at the server
machine. For example, a user clicks a button displayed in the browser. A Click event
is raised. The browser handles this client-side event by posting it to the server.
The server has a subroutine describing what to do when the event is raised; it is
called the event-handler. Therefore, when the event message is transmitted to the
server, it checks whether the Click event has an associated event handler. If it has,
the event handler is executed.
EventArguments
ASP.NET event handlers generally take two parameters and return void. The first
parameter represents the object raising the event and the second parameter is event
argument.
The general syntax of an event is:
private void EventName (object sender, EventArgs e);
ApplicationandSessionEvents
The most important application events are:
 Application_Start - It is raised when the application/website is started
 Application_End - It is raised when the application/website is stopped.
Similarly, the most used Session events are:
 Session_Start - It is raised when a user first requests a page from the
application.
 Session_End - It is raised when the session ends.
PageandControlEvents
Common page and control events are:
 DataBinding – It is raised when a control binds to a data source.
5. EVENT HANDLING

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18
 Disposed – It is raised when the page or the control is released.
 Error - It is a page event, occurs when an unhandled exception is thrown.
 Init – It is raised when the page or the control is initialized.
 Load – It is raised when the page or a control is loaded.
 PreRender – It is raised when the page or the control is to be rendered.
 Unload – It is raised when the page or control is unloaded from memory.
EventHandlingUsingControls
All ASP.NET controls are implemented as classes, and they have events which are
fired when a user performs a certain action on them. For example, when a user clicks
a button the 'Click' event is generated. For handling events, there are in-built
attributes and event handlers. Event handler is coded to respond to an event and
take appropriate action on it.
By default, Visual Studio creates an event handler by including a Handles clause on
the Sub procedure. This clause names the control and event that the procedure
handles.
The ASP tag for a button control:
<asp:Button ID="btnCancel" runat="server" Text="Cancel" />
The event handler for the Click event:
Protected Sub btnCancel_Click(ByVal sender As Object,
ByVal e As System.EventArgs)
Handles btnCancel.Click
End Sub
An event can also be coded without Handles clause. Then, the handler must be named
according to the appropriate event attribute of the control.
The ASP tag for a button control:
<asp:Button ID="btnCancel" runat="server" Text="Cancel"
Onclick="btnCancel_Click" />
The event handler for the Click event:
Protected Sub btnCancel_Click(ByVal sender As Object,
ByVal e As System.EventArgs)

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19
End Sub
The common control events are:
Event Attribute Controls
Click OnClick Button, image button, link
button, image map
Command OnCommand Button, image button, link
button
TextChanged OnTextChanged Text box
SelectedIndexChanged OnSelectedIndexChanged Drop-down list, list box, radio
button list, check box list.
CheckedChanged OnCheckedChanged Check box, radio button
Some events cause the form to be posted back to the server immediately, these are
called the postback events. For example, the click event such as Button.Click.
Some events are not posted back to the server immediately, these are called non-
postback events. For example, the change events or selection events such as
TextBox.TextChanged or CheckBox.CheckedChanged. The nonpostback events could
be made to post back immediately by setting their AutoPostBack property to true.
DefaultEvents
The default event for the Page object is Load event. Similarly, every control has a
default event. For example, default event for the button control is the Click event.
The default event handler could be created in Visual Studio, just by double clicking
the control in design view. The following table shows some of the default events for
common controls:
Control Default Event
AdRotator AdCreated
BulletedList Click
Button Click

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20
Calender SelectionChanged
CheckBox CheckedChanged
CheckBoxList SelectedIndexChanged
DataGrid SelectedIndexChanged
DataList SelectedIndexChanged
DropDownList SelectedIndexChanged
HyperLink Click
ImageButton Click
ImageMap Click
LinkButton Click
ListBox SelectedIndexChanged
Menu MenuItemClick
RadioButton CheckedChanged
RadioButtonList SelectedIndexChanged
Example
This example includes a simple page with a label control and a button control on it.
As the page events such as Page_Load, Page_Init, Page_PreRender etc. take place,
it sends a message, which is displayed by the label control. When the button is
clicked, the Button_Click event is raised and that also sends a message to be
displayed on the label.
Create a new website and drag a label control and a button control on it from the
control tool box. Using the properties window, set the IDs of the controls as
.lblmessage. and .btnclick respectively. Set the Text property of the Button control
as 'Click'.
The markup file (.aspx):

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Inherits="eventdemo._Default" %>
</head>
<body>
<div>
<asp:Label ID="lblmessage" runat="server" >
</asp:Label>
<br />
<br />
<br />
<asp:Button ID="btnclick" runat="server" Text="Click"
onclick="btnclick_Click" />
</div>
</form>
</body>
</html>
Double click on the design view to move to the code behind file. The Page_Load event
is automatically created without any code in it. Write down the following self-
explanatory code lines:
using System;

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using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
namespace eventdemo
{
public partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
lblmessage.Text += "Page load event handled. <br />";
if (Page.IsPostBack)
{
lblmessage.Text += "Page post back event handled.<br/>";
}
}
protected void Page_Init(object sender, EventArgs e)
{
lblmessage.Text += "Page initialization event handled.<br/>";
}

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protected void Page_PreRender(object sender, EventArgs e)
{
lblmessage.Text += "Page prerender event handled. <br/>";
}
protected void btnclick_Click(object sender, EventArgs e)
{
lblmessage.Text += "Button click event handled. <br/>";
}
}
}
Execute the page. The label shows page load, page initialization, and the page pre-
render events. Click the button to see effect:

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24
We have studied the page life cycle and how a page contains various controls. The
page itself is instantiated as a control object. All web forms are basically instances of
the ASP.NET Page class. The page class has the following extremely useful properties
that correspond to intrinsic objects:
 Session
 Application
 Cache
 Request
 Response
 Server
 User
 Trace
We will discuss each of these objects in due time. In this tutorial, we will explore the
Server object, the Request object, and the Response object.
ServerObject
The Server object in ASP.NET is an instance of the System.Web.HttpServerUtility
class. The HttpServerUtility class provides numerous properties and methods to
perform various jobs.
Properties and Methods of the Server object
The methods and properties of the HttpServerUtility class are exposed through the
intrinsic Server object provided by ASP.NET.
The following table provides a list of the properties:
Property Description
MachineName Name of server computer
ScriptTimeOut Gets and sets the request time-out value in seconds.
The following table provides a list of some important methods:
6. SERVER SIDE

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25
Method Description
CreateObject(String)
Creates an instance of the COM object identified
by its ProgID (Programmatic ID)
CreateObject(Type)
Creates an instance of the COM object identified
by its Type.
Equals(Object)
Determines whether the specified object is equal
to the current object.
Execute(String)
Executes the handler for the specified virtual
path in the context of the current request.
Execute(String, Boolean) Executes the handler for the specified virtual
path in the context of the current request and
specifies whether to clear the QueryString and
Form collections.
GetLastError Returns the previous exception.
GetType Gets the Type of the current instance.
HtmlEncode
Changes an ordinary string into a string with
legal HTML characters.
HtmlDecode Converts an Html string into an ordinary string
ToString
Returns a String that represents the current
Object
Transfer(String)
For the current request, terminates execution of
the current page and starts execution of a new
page by using the specified URL path of the
page.
UrlDecode Converts an URL string into an ordinary string
UrlEncodeToken
Works same as UrlEncode, but on a byte array
that contains Base64-encoded data

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UrlDecodeToken
Works same as UrlDecode, but on a byte array
that contains Base64-encoded data
MapPath
Return the physical path that corresponds to a
specified virtual file path on the server
Transfer
Transfers execution to another web page in the
current application
RequestObject
The request object is an instance of the System.Web.HttpRequest class. It represents
the values and properties of the HTTP request that makes the page loading into the
browser.
The information presented by this object is wrapped by the higher level abstractions
(the web control model). However, this object helps in checking some information
such as the client browser and cookies.
Properties and Methods of the Request Object
The following table provides some noteworthy properties of the Request object:
AcceptTypes Gets a string array of client-supported MIME accept types.
ApplicationPath Gets the ASP.NET application's virtual application root
path on the server.
Browser Gets or sets information about the requesting client's
browser capabilities.
ContentEncoding Gets or sets the character set of the entity-body.
ContentLength Specifies the length, in bytes, of content sent by the client.
ContentType Gets or sets the MIME content type of the incoming
request.
Cookies Gets a collection of cookies sent by the client.

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27
FilePath Gets the virtual path of the current request.
Files Gets the collection of files uploaded by the client, in
multipart MIME format.
Form Gets a collection of form variables.
Headers Gets a collection of HTTP headers.
HttpMethod Gets the HTTP data transfer method (such as GET, POST,
or HEAD) used by the client.
InputStream Gets the contents of the incoming HTTP entity body.
IsSecureConnection Gets a value indicating whether the HTTP connection uses
secure sockets (that is, HTTPS).
QueryString Gets the collection of HTTP query string variables.
RawUrl Gets the raw URL of the current request.
RequestType Gets or sets the HTTP data transfer method (GET or POST)
used by the client.
ServerVariables Gets a collection of Web server variables.
TotalBytes Gets the number of bytes in the current input stream.
Url Gets information about the URL of the current request.
UrlReferrer Gets information about the URL of the client's previous
request that is linked to the current URL.
UserAgent Gets the raw user agent string of the client browser.
UserHostAddress Gets the IP host address of the remote client.
UserHostName Gets the DNS name of the remote client.
UserLanguages Gets a sorted string array of client language preferences.

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Method Description
BinaryRead Performs a binary read of a specified number of bytes
from the current input stream.
Equals(Object) Determines whether the specified object is equal to the
current object. (Inherited from Object.)
MapImageCoordinates Maps an incoming image-field form parameter to
appropriate x-coordinate and y-coordinate values.
MapPath(String) Maps the specified virtual path to a physical path.
SaveAs Saves an HTTP request to disk.
ToString Returns a String that represents the current object
ValidateInput Causes validation to occur for the collections accessed
through the Cookies, Form, and QueryString properties.
ResponseObject
The Response object represents the server's response to the client request. It is an
instance of the System.Web.HttpResponse class.
In ASP.NET, the response object does not play any vital role in sending HTML text to
the client, because the server-side controls have nested object oriented methods for
rendering themselves.
However, the HttpResponse object still provides some important functionalities, like
the cookie feature and the Redirect() method. The Response.Redirect() method
allows transferring the user to another page, inside as well as outside the application.
It requires a round trip.
Properties and Methods of the Response Object
The following table provides some noteworthy properties of the Response object:

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Buffer Gets or sets a value indicating whether to buffer the output
and send it after the complete response is finished processing.
BufferOutput Gets or sets a value indicating whether to buffer the output
and send it after the complete page is finished processing.
Charset Gets or sets the HTTP character set of the output stream.
ContentEncoding Gets or sets the HTTP character set of the output stream.
ContentType Gets or sets the HTTP MIME type of the output stream.
Cookies Gets the response cookie collection.
Expires Gets or sets the number of minutes before a page cached on
a browser expires.
ExpiresAbsolute Gets or sets the absolute date and time at which to remove
cached information from the cache
HeaderEncoding Gets or sets an encoding object that represents the encoding
for the current header output stream.
Headers Gets the collection of response headers.
IsClientConnected Gets a value indicating whether the client is still connected to
the server.
Output Enables output of text to the outgoing HTTP response stream.
OutputStream Enables binary output to the outgoing HTTP content body.
RedirectLocation Gets or sets the value of the Http Location header.
Status Sets the status line that is returned to the client.
StatusCode Gets or sets the HTTP status code of the output returned to
the client.

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30
StatusDescription Gets or sets the HTTP status string of the output returned to
the client.
SubStatusCode Gets or sets a value qualifying the status code of the response.
SuppressContent Gets or sets a value indicating whether to send HTTP content
to the client.
Method Description
AddHeader Adds an HTTP header to the output stream. AddHeader is
provided for compatibility with earlier versions of ASP.
AppendCookie Infrastructure adds an HTTP cookie to the intrinsic cookie
collection.
AppendHeader Adds an HTTP header to the output stream.
AppendToLog Adds custom log information to the Internet Information
Services (IIS) log file.
BinaryWrite Writes a string of binary characters to the HTTP output
stream.
ClearContent Clears all content output from the buffer stream.
Close Closes the socket connection to a client.
End Sends all currently buffered output to the client, stops
execution of the page, and raises the EndRequest event.
Equals(Object) Determines whether the specified Object is equal to the
current Object
Flush Sends all currently buffered output to the client.

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31
Pics Appends a HTTP PICS-Label header to the output stream.
Redirect(String) Redirects a request to a new URL and specifies the new URL.
Redirect(String,
Boolean)
Redirects a client to a new URL. Specifies the new URL and
whether execution of the current page should terminate.
SetCookie Updates an existing cookie in the cookie collection.
ToString Returns a String that represents the current Object.
TransmitFile(String) Writes the specified file directly to an HTTP response output
stream, without buffering it in memory.
Write(Char) Writes a character to an HTTP response output stream.
Write(Object) Writes an object to an HTTP response stream.
Write(String) Writes a string to an HTTP response output stream.
WriteFile(String) Writes the contents of the specified file directly to an HTTP
response output stream as a file block.
WriteFile(String,
Boolean)
Writes the contents of the specified file directly to an HTTP
response output stream as a memory block.
Example
The following simple example has a text box control where the user can enter name,
a button to send the information to the server, and a label control to display the URL
of the client computer.
The content file:
Inherits="server_side._Default" %>

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32
</head>
<body>
<div>
Enter your name:<br />
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
<asp:Button ID="Button1" runat="server"
OnClick="Button1_Click" Text="Submit" />
<br />
<asp:Label ID="Label1" runat="server"/>
</div>
</form>
</body>
</html>
The code behind Button1_Click:
{
if (!String.IsNullOrEmpty(TextBox1.Text))
{
// Access the HttpServerUtility methods through
// the intrinsic Server object.
Label1.Text = "Welcome, " +
Server.HtmlEncode(TextBox1.Text) +

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33
".<br/> The url is " +
Server.UrlEncode(Request.Url.ToString());
}
}
Run the page to see the following result:

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34
Controls are small building blocks of the graphical user interface, which include text
boxes, buttons, check boxes, list boxes, labels, and numerous other tools. Using
these tools, the users can enter data, make selections and indicate their preferences.
Controls are also used for structural jobs, like validation, data access, security,
creating master pages, and data manipulation.
ASP.NET uses five types of web controls:
 HTML controls
 HTML Server controls
 ASP.NET Server controls
 ASP.NET Ajax Server controls
 User controls and custom controls
ASP.NET server controls are the primary controls used in ASP.NET. These controls
can be grouped into the following categories:
 Validation controls - These are used to validate user input and they work by
running client-side script.
 Data source controls - These controls provides data binding to different data
sources.
 Data view controls - These are various lists and tables, which can bind to
data from data sources for displaying.
 Personalization controls - These are used for personalization of a page
according to the user preferences, based on user information.
 Login and security controls - These controls provide user authentication.
 Master pages - These controls provide consistent layout and interface
throughout the application.
 Navigation controls - These controls help in navigation. For example,
menus, tree view etc.
 Rich controls - These controls implement special features. For example,
AdRotator, FileUpload, and Calendar control.
The syntax for using server controls is:
<asp:controlType ID ="ControlID"
runat="server"
Property1=value1 [Property2=value2] />
7. SERVER CONTROLS

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35
In addition, visual studio has the following features to help produce error-free coding:
 Dragging and dropping of controls in design view
 IntelliSense feature that displays and auto-completes the properties
 The properties window to set the property values directly
PropertiesoftheServerControls
ASP.NET server controls with a visual aspect are derived from the WebControl class
and inherit all the properties, events, and methods of this class.
The WebControl class itself and some other server controls that are not visually
rendered are derived from the System.Web.UI.Control class. For example,
PlaceHolder control or XML control.
ASP.NET server controls inherit all properties, events, and methods of the WebControl
and System.Web.UI.Control class.
The following table shows the inherited properties common to all server controls:
AccessKey
Pressing this key with the Alt key moves focus to the
control
Attributes
It is the collection of arbitrary attributes (for rendering
only) that do not correspond to properties on the
control.
BackColor Background color.
BindingContainer The control that contains this control's data binding.
BorderColor Border color.
BorderStyle Border style.
BorderWidth Border width.
CausesValidation Indicates if it causes validation.
ChildControlCreated
It indicates whether the server control's child controls
have been created.

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36
ClientID Control ID for HTML markup.
Context
The HttpContext object associated with the server
control.
Controls Collection of all controls contained within the control.
ControlStyle The style of the Web server control.
CssClass CSS class
DataItemContainer
Gets a reference to the naming container if the naming
container implements IDataItemContainer.
DataKeysContainer
Gets a reference to the naming container if the naming
container implements IDataKeysControl.
DesignMode
It indicates whether the control is being used on a
design surface.
DisabledCssClass
Gets or sets the CSS class to apply to the rendered
HTML element when the control is disabled.
Enabled Indicates whether the control is grayed out.
EnableTheming Indicates whether theming applies to the control.
EnableViewState
Indicates whether the view state of the control is
maintained.
Events Gets a list of event handler delegates for the control.
Font Font.
Forecolor Foreground color.
HasAttributes Indicates whether the control has attributes set.
HasChildViewState
Indicates whether the current server control's child
controls have any saved view-state settings.

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37
Height Height in pixels or %.
ID Identifier for the control.
IsChildControlStateClear
ed
Indicates whether controls contained within this control
have control state.
IsEnabled Gets a value indicating whether the control is enabled
IsTrackingViewState
It indicates whether the server control is saving changes
to its view state.
IsViewStateEnabled
It indicates whether view state is enabled for this
control.
LoadViewStateById
It indicates whether the control participates in loading
its view state by ID instead of index.
Page Page containing the control.
Parent Parent control.
RenderingCompatibility
It specifies the ASP.NET version that the rendered HTML
will be compatible with.
Site
The container that hosts the current control when
rendered on a design surface.
SkinID Gets or sets the skin to apply to the control.
Style
Gets a collection of text attributes that will be rendered
as a style attribute on the outer tag of the Web server
control.
TabIndex Gets or sets the tab index of the Web server control.
TagKey
Gets the HtmlTextWriterTag value that corresponds to
this Web server control.
TagName Gets the name of the control tag.

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38
TemplateControl The template that contains this control.
TemplateSourceDirectory
Gets the virtual directory of the page or control
containing this control.
ToolTip
Gets or sets the text displayed when the mouse pointer
hovers over the web server control.
UniqueID Unique identifier
ViewState
Gets a dictionary of state information that saves and
restores the view state of a server control across
multiple requests for the same page.
ViewStateIgnoreCase
It indicates whether the StateBag object is case-
insensitive.
ViewStateMode Gets or sets the view-state mode of this control.
Visible It indicates whether a server control is visible.
Width Gets or sets the width of the Web server control.
MethodsoftheServerControls
The following table provides the methods of the server controls:
Method Description
AddAttributesToRender
Adds HTML attributes and styles that need to be
rendered to the specified HtmlTextWriterTag.
AddedControl
Called after a child control is added to the Controls
collection of the control object.
AddParsedSubObject
Notifies the server control that an element, either XML
or HTML, was parsed, and adds the element to the
server control's control collection.

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39
ApplyStyleSheetSkin
Applies the style properties defined in the page style
sheet to the control.
ClearCachedClientID Infrastructure. Sets the cached ClientID value to null.
ClearChildControlState
Deletes the control-state information for the server
control's child controls.
ClearChildState
Deletes the view-state and control-state information
for all the server control's child controls.
ClearChildViewState
Deletes the view-state information for all the server
control's child controls.
CreateChildControls Used in creating child controls.
CreateControlCollection
Creates a new ControlCollection object to hold the
child controls.
CreateControlStyle
Creates the style object that is used to implement all
style related properties.
DataBind
Binds a data source to the server control and all its
child controls.
DataBind(Boolean)
Binds a data source to the server control and all its
child controls with an option to raise the DataBinding
event.
DataBindChildren
Binds a data source to the server control's child
controls.
Dispose
Enables a server control to perform final clean up
before it is released from memory.
EnsureChildControls
Determines whether the server control contains child
controls. If it does not, it creates child controls.
EnsureID
Creates an identifier for controls that do not have an
identifier.

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40
Equals(Object)
Determines whether the specified object is equal to
the current object.
Finalize
Allows an object to attempt to free resources and
perform other cleanup operations before the object is
reclaimed by garbage collection.
FindControl(String)
Searches the current naming container for a server
control with the specified id parameter.
FindControl(String, Int32)
Searches the current naming container for a server
control with the specified id and an integer
Focus Sets input focus to a control.
GetDesignModeState Gets design-time data for a control.
GetType Gets the type of the current instance.
GetUniqueIDRelativeTo
Returns the prefixed portion of the UniqueID property
of the specified control.
HasControls
Determines if the server control contains any child
controls.
HasEvents
Indicates whether events are registered for the control
or any child controls.
IsLiteralContent
Determines if the server control holds only literal
content.
LoadControlState Restores control-state information.
LoadViewState Restores view-state information.
MapPathSecure
Retrieves the physical path that a virtual path, either
absolute or relative, maps to.
MemberwiseClone Creates a shallow copy of the current object.

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41
MergeStyle
Copies any nonblank elements of the specified style to
the web control, but does not overwrite any existing
style elements of the control.
OnBubbleEvent
Determines whether the event for the server control is
passed up the page's UI server control hierarchy.
OnDataBinding Raises the data binding event.
OnInit Raises the Init event.
OnLoad Raises the Load event.
OnPreRender Raises the PreRender event.
OnUnload Raises the Unload event.
OpenFile Gets a Stream used to read a file.
RemovedControl
Called after a child control is removed from the
controls collection of the control object.
Render Renders the control to the specified HTML writer.
RenderBeginTag
Renders the HTML opening tag of the control to the
specified writer.
RenderChildren
Outputs the contents of a server control's children to
a provided HtmlTextWriter object, which writes the
contents to be rendered on the client.
RenderContents
Renders the contents of the control to the specified
writer.
RenderControl(HtmlTextW
riter)
Outputs server control content to a provided
HtmlTextWriter object and stores tracing information
about the control if tracing is enabled.
RenderEndTag
Renders the HTML closing tag of the control into the
specified writer.

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42
ResolveAdapter
Gets the control adapter responsible for rendering the
specified control.
SaveControlState
Saves any server control state changes that have
occurred since the time the page was posted back to
the server.
SaveViewState
Saves any state that was modified after the
TrackViewState method was invoked.
SetDesignModeState Sets design-time data for a control.
ToString Returns a string that represents the current object.
TrackViewState
Causes the control to track changes to its view state
so that they can be stored in the object's view state
property.
Example
Let us look at a particular server control - a tree view control. A Tree view control
comes under navigation controls. Other Navigation controls are: Menu control and
SiteMapPath control.
Add a tree view control on the page. Select Edit Nodes... from the tasks. Edit each of
the nodes using the Tree view node editor as shown:

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43
Once you have created the nodes, it looks like the following in design view:
The AutoFormat... task allows you to format the tree view as shown:
Add a label control and a text box control on the page and name them lblmessage
and txtmessage respectively.
Write a few lines of code to ensure that when a particular node is selected, the label
control displays the node text and the text box displays all child nodes under it, if
any. The code behind the file should look like this:

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44
using System;
using System.Data;
using System.Linq;
using System.Web;
namespace eventdemo
{
public partial class treeviewdemo : System.Web.UI.Page
{
{
txtmessage.Text = " ";
}
protected void TreeView1_SelectedNodeChanged(object sender, EventArgs e)
{
lblmessage.Text = "Selected node changed to: " +
TreeView1.SelectedNode.Text;
TreeNodeCollection childnodes = TreeView1.SelectedNode.ChildNodes;
if(childnodes != null)

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45
{
foreach (TreeNode t in childnodes)
{
txtmessage.Text += t.Value;
}
}
}
}
}
Execute the page to see the effects. You will be able to expand and collapse the
nodes.

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46
The HTML server controls are basically the standard HTML controls enhanced to
enable server side processing. The HTML controls such as the header tags, anchor
tags, and input elements are not processed by the server but are sent to the browser
for display.
They are specifically converted to a server control by adding the attribute
runat="server" and adding an id attribute to make them available for server-side
processing.
For example, consider the HTML input control:
<input type="text" size="40">
It could be converted to a server control, by adding the runat and id attribute:
<input type="text" id="testtext" size="40" runat="server">
AdvantagesofusingHTMLServerControls
Although ASP.NET server controls can perform every job accomplished by the HTML
server controls, the later controls are useful in the following cases:
 Using static tables for layout purposes.
 Converting a HTML page to run under ASP.NET.
The following table describes the HTML server controls:
Control Name HTML tag
HtmlHead <head>element
HtmlInputButton <input type=button|submit|reset>
HtmlInputCheckbox <input type=checkbox>
HtmlInputFile <input type = file>
HtmlInputHidden <input type = hidden>
HtmlInputImage <input type = image>
8. HTML SERVER

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HtmlInputPassword <input type = password>
HtmlInputRadioButton <input type = radio>
HtmlInputReset <input type = reset>
HtmlText <input type = text|password>
HtmlImage <img> element
HtmlLink <link> element
HtmlAnchor <a> element
HtmlButton <button> element
HtmlButton <button> element
HtmlForm <form> element
HtmlTable <table> element
HtmlTableCell <td> and <th>
HtmlTableRow <tr> element
HtmlTitle <title> element
HtmlSelect <select> element
HtmlGenericControl All HTML controls not listed
Example
The following example uses a basic HTML table for layout. It uses text boxes for
getting input from the users such as name, address, city, state, etc. It also has a
button control, which is clicked to get the user data displayed in the last row of the
table.
The page should look like this in the design view:

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The code for the content page shows the use of the HTML table element for layout.
Inherits="htmlserver._Default" %>
<style type="text/css">
.style1
{
width: 156px;
}
.style2
{
width: 332px;

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49
}
</style>
</head>
<body>
<div>
<table style="width: 54%;">
<tr>
<td class="style1">Name:</td>
<td class="style2">
<asp:TextBox ID="txtname" runat="server" style="width:230px">
</asp:TextBox>
</td>
</tr>
<tr>
<td class="style1">Street</td>
<td class="style2">
<asp:TextBox ID="txtstreet" runat="server" style="width:230px">
</asp:TextBox>
</td>
</tr>
<tr>
<td class="style1">City</td>
<td class="style2">
<asp:TextBox ID="txtcity" runat="server" style="width:230px">
</asp:TextBox>
</td>
</tr>

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<tr>
<td class="style1">State</td>
<td class="style2">
<asp:TextBox ID="txtstate" runat="server" style="width:230px">
</asp:TextBox>
</td>
</tr>
<tr>
<td class="style1"> </td>
<td class="style2"></td>
</tr>
<tr>
<td class="style1"></td>
<td ID="displayrow" runat ="server" class="style2">
</td>
</tr>
</table>
</div>
onclick="Button1_Click" Text="Click" />
</form>
</body>
</html>
The code behind the button control:
{
string str = "";
str += txtname.Text + "<br />";

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str += txtstreet.Text + "<br />";
str += txtcity.Text + "<br />";
str += txtstate.Text + "<br />";
displayrow.InnerHtml = str;
}
Observe the following:
 The standard HTML tags have been used for the page layout.
 The last row of the HTML table is used for data display. It needed server side
processing, so an ID attribute and the runat attribute has been added to it.

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ASP.NET client side coding has two aspects:
 Client side script: It runs on the browser and in turn speeds up the execution
of page. For example, client side data validation which can catch invalid data
and warn the user accordingly without making a round trip to the server.
 Client side source code: ASP.NET pages generate this. For example, the
HTML source code of an ASP.NET page contains a number of hidden fields and
automatically injected blocks of JavaScript code, which keeps information like
view state or does other jobs to make the page work.
ClientSideScripts
All ASP.NET server controls allow calling client side code written using JavaScript or
VBScript. Some ASP.NET server controls use client side scripting to provide response
to the users without posting back to the server.For example, the validation controls.
Apart from these scripts, the Button control has a property OnClientClick, which
allows executing client-side script, when the button is clicked.
The traditional and server HTML controls have the following events that can execute
a script when they are raised:
Event Description
onblur When the control loses focus
onfocus When the control receives focus
onclick When the control is clicked
onchange When the value of the control changes
onkeydown When the user presses a key
onkeypress When the user presses an alphanumeric key
onkeyup When the user releases a key
onmouseover When the user moves the mouse pointer over the control
9. CLIENT SIDE

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onserverclick It raises the ServerClick event of the control, when the
control is clicked
ClientSideSourceCode
We have already discussed that ASP.NET pages are generally written in two files:
 The content file or the markup file (.aspx)
 The code-behind file
The content file contains the HTML or ASP.NET control tags and literals to form the
structure of the page. The code behind file contains the class definition. At runtime,
the content file is parsed and transformed into a page class.
This class, along with the class definition in the code file, and system generated code,
together make the executable code (assembly) that processes all posted data,
generates response, and sends it back to the client.
Consider the simple page:
Inherits="clientside._Default" %>
</head>
<body>
<div>
<asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
OnClick="Button1_Click" Text="Click" />
</div>
<hr />
<h3><asp:Label ID="Msg" runat="server" Text=""></asp:Label>
</h3>

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</form>
</body>
</html>
When this page is run on the browser, the View Source option shows the HTML page
sent to the browser by the ASP.NET runtime:
<head><title>
Untitled Page
</title></head>
<body>
<form name="form1" method="post" action="Default.aspx" id="form1">
<div>
<input type="hidden" name="__VIEWSTATE" id="__VIEWSTATE"
value="/wEPDwUKMTU5MTA2ODYwOWRk31NudGDgvhhA7joJum9Qn5RxU2M=" />
</div>
<div>
<input type="hidden" name="__EVENTVALIDATION"
id="__EVENTVALIDATION"
value="/wEWAwKpjZj0DALs0bLrBgKM54rGBhHsyM61rraxE+KnBTCS8cd1QDJ/"/>
</div>
<div>
<input name="TextBox1" type="text" id="TextBox1" />
<input type="submit" name="Button1" value="Click" id="Button1" />
</div>
<hr />
<h3><span id="Msg"></span></h3>
</form>
</body>

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</html>
If you go through the code properly, you can see that first two <div> tags contain
the hidden fields which store the view state and validation information.

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In this chapter, we will discuss the basic controls available in ASP.NET.
ButtonControls
ASP .Net provides three types of button control:
 Button - It displays text within a rectangular area
 Link button - It displays text that looks like a hyperlink
 Image button – It displays an image.
When a user clicks a button, two events are raised: Click and Command.
Basic syntax of button control:
onclick="Button1_Click" Text="Click" />
Common properties of the button control:
Text The text displayed on the button. This is for button and link
button controls only.
ImageUrl For image button control only. The image to be displayed
for the button.
AlternateText For image button control only. The text to be displayed if
the browser cannot display the image.
CausesValidation Determines whether page validation occurs when a user
clicks the button. The default is true.
CommandName A string value that is passed to the command event when
a user clicks the button.
CommandArgument A string value that is passed to the command event when
a user clicks the button.
10. BASIC CONTROLS

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57
PostBackUrl The URL of the page that is requested when the user clicks
the button.
TextBoxesandLabels
Text box controls are typically used to accept input from the user. A text box control
can accept one or more lines of text depending upon the settings of the TextMode
attribute.
Label controls provide an easy way to display text which can be changed from one
execution of a page to the next. If you want to display text that does not change,
you use the literal text.
Basic syntax of text control:
<asp:TextBox ID="txtstate" runat="server" ></asp:TextBox
Common properties of the text box and labels:
TextMode Specifies the type of text box. SingleLine creates a standard text
box, MultiLIne creates a text box that accepts more than one line of
text and the Password causes the characters that are entered to be
masked. The default is SingleLine.
Text The text content of the text box.
MaxLength The maximum number of characters that can be entered into the
text box.
Wrap It determines whether or not text wraps automatically for multi-line
text box; default is true.
ReadOnly Determines whether the user can change the text in the box; default
is false, i.e., the user can change the text.
Columns The width of the text box in characters. The actual width is
determined based on the font that is used for the text entry.
Rows The height of a multi-line text box in lines. The default value is 0,
means a single line text box.

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The mostly used attribute for a label control is 'Text', which implies the text displayed
on the label.
CheckBoxesandRadioButtons
A check box displays a single option that the user can either check or uncheck and
radio buttons present a group of options from which the user can select just one
option.
To create a group of radio buttons, you specify the same name for the GroupName
attribute of each radio button in the group. If more than one group is required in a
single form, then specify a different group name for each group.
If you want check box or radio button to be selected when the form is initially
displayed, set its Checked attribute to true. If the Checked attribute is set to true for
multiple radio buttons in a group, then only the last one is considered as true.
Basic syntax of check box:
<asp:CheckBox ID= "chkoption" runat= "Server">
</asp:CheckBox>
Basic syntax of radio button:
<asp:RadioButton ID= "rdboption" runat= "Server">
</asp: RadioButton>
Common properties of check boxes and radio buttons:
Text The text displayed next to the check box or radio button.
Checked Specifies whether it is selected or not, default is false.
GroupName Name of the group the control belongs to.
ListControls
ASP.NET provides the following controls:
 Drop-down list
 List box
 Radio button list

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 Check box list
 Bulleted list
These control let a user choose from one or more items from the list. List boxes and
drop-down lists contain one or more list items. These lists can be loaded either by
code or by the ListItem collection editor.
Basic syntax of list box control:
<asp:ListBox ID="ListBox1"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="ListBox1_SelectedIndexChanged">
</asp:ListBox>
Basic syntax of drop-down list control:
<asp:DropDownList ID="DropDownList1"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>
Common properties of list box and drop-down lists:
Items The collection of ListItem objects that represents the items in the
control. This property returns an object of type ListItemCollection.
Rows Specifies the number of items displayed in the box. If actual list
contains more rows than displayed then a scroll bar is added.

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60
SelectedIndex The index of the currently selected item. If more than one item is
selected, then the index of the first selected item. If no item is
selected, the value of this property is -1.
SelectedValue The value of the currently selected item. If more than one item is
selected, then the value of the first selected item. If no item is
selected, the value of this property is an empty string ("").
SelectionMode Indicates whether a list box allows single selections or multiple
selections.
Common properties of each list item objects:
Text The text displayed for the item.
Selected Indicates whether the item is selected.
Value A string value associated with the item.
It is important to notes that:
 To work with the items in a drop-down list or list box, you use the Items
property of the control. This property returns a ListItemCollection object which
contains all the items of the list.
 The SelectedIndexChanged event is raised when the user selects a different
item from a drop-down list or list box.
TheListItemCollectionObject
The ListItemCollection object is a collection of ListItem objects. Each ListItem object
represents one item in the list. Items in a ListItemCollection are numbered from 0.
When the items into a list box are loaded using strings like:
lstcolor.Items.Add("Blue"), then both the Text and Value properties of the list item
are set to the string value you specify. To set it differently you must create a list item
object and then add that item to the collection.
The ListItem Collection Editor is used to add item to a drop-down list or list box. This
is used to create a static list of items. To display the collection editor, select edit item
from the smart tag menu, or select the control and then click the ellipsis button from
the Item property in the properties window.

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Common properties of ListItemCollection:
Item(integer) A ListItem object that represents the item at the
specified index.
Count The number of items in the collection.
Common methods of ListItemCollection:
Methods Description
Add(string) Adds a new item at the end of the collection and
assigns the string parameter to the Text property of
the item.
Add(ListItem) Adds a new item at the end of the collection.
Insert(integer, string) Inserts an item at the specified index location in the
collection and assigns string parameter to the text
property of the item.
Insert(integer, ListItem) Inserts the item at the specified index location in the
collection.
Remove(string) Removes the item with the text value same as the
string.
Remove(ListItem) Removes the specified item.
RemoveAt(integer) Removes the item at the specified index as the
integer.
Clear Removes all the items of the collection.
FindByValue(string) Returns the item whose value is same as the string.
FindByValue(Text) Returns the item whose text is same as the string.

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RadioButtonlistandCheckBoxList
A radio button list presents a list of mutually exclusive options. A check box list
presents a list of independent options. These controls contain a collection of ListItem
objects that could be referred to through the Items property of the control.
Basic syntax of radio button list:
<asp:RadioButtonList ID="RadioButtonList1"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged">
</asp:RadioButtonList>
Basic syntax of check box list:
<asp:CheckBoxList ID="CheckBoxList1"
runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="CheckBoxList1_SelectedIndexChanged">
</asp:CheckBoxList>
Common properties of check box and radio button list:
RepeatLayout This attribute specifies whether the table tags or the normal
html flow to use while formatting the list when it is rendered.
The default is Table.
RepeatDirection It specifies the direction in which the controls to be
repeated. The values available are Horizontal and Vertical.
Default is Vertical.
RepeatColumns It specifies the number of columns to use when repeating
the controls; default is 0.

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BulletedlistsandNumberedLists
The bulleted list control creates bulleted lists or numbered lists. These controls
contain a collection of ListItem objects that could be referred to through the Items
property of the control.
Basic syntax of a bulleted list:
<asp:BulletedList ID="BulletedList1" runat="server">
</asp:BulletedList>
Common properties of bulleted list:
BulletStyle This property specifies the style and looks of the bullets, or
numbers.
RepeatDirection It specifies the direction in which the controls to be
repeated. The values available are Horizontal and Vertical.
Default is Vertical.
RepeatColumns It specifies the number of columns to use when repeating
the controls; default is 0.
HyperLinkControl
The HyperLink control is like the HTML <a> element.
Basic syntax for a hyperlink control:
<asp:HyperLink ID="HyperLink1" runat="server">
HyperLink
</asp:HyperLink>
It has the following important properties:
ImageUrl Path of the image to be displayed by the control.
NavigateUrl Target link URL.

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64
Text The text to be displayed as the link.
Target The window or frame which loads the linked page.
ImageControl
The image control is used for displaying images on the web page, or some alternative
text, if the image is not available.
Basic syntax for an image control:
<asp:Image ID="Image1" runat="server">
It has the following important properties:
AlternateText Alternate text to be displayed in absence of the image.
ImageAlign Alignment options for the control.
ImageUrl Path of the image to be displayed by the control.

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ASP.NET directives are instructions to specify optional settings, such as registering a
custom control and page language. These settings describe how the web forms
(.aspx) or user controls (.ascx) pages are processed by the .Net framework.
The syntax for declaring a directive is:
<%@ directive_name attribute=value [attribute=value] %>
In this section, we will just introduce the ASP.NET directives and we will use most of
these directives throughout the tutorials.
TheApplicationDirective
The Application directive defines application-specific attributes. It is provided at the
top of the global.aspx file.
The basic syntax of Application directive is:
<%@ Application Language="C#" %>
The attributes of the Application directive are:
Attributes Description
Inherits The name of the class from which to inherit
Description The text description of the application. Parsers and
compilers ignore this.
Language The language used in code blocks.
TheAssemblyDirective
The Assembly directive links an assembly to the page or the application at parse
time. This could appear either in the global.asax file for application-wide linking, in
the page file, or a user control file for linking to a page or user control.
The basic syntax of Assembly directive is:
11. DIRECTIVES

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66
<%@ Assembly Name ="myassembly" %>
The attributes of the Assembly directive are:
Name The name of the assembly to be linked
Src The path to the source file to be linked and compiled
dynamically
TheControlDirective
The control directive is used with the user controls and appears in the user control
(.ascx) files.
The basic syntax of Control directive is:
<%@ Control Language="C#" EnableViewState="false" %>
The attributes of the Control directive are:
AutoEventWireup The Boolean value that enables or disables automatic
association of events to handlers.
ClassName The file name for the control.
Debug The Boolean value that enables or disables compiling with
debug symbols
Description The text description of the control page, ignored by
compiler.
EnableViewState The Boolean value that indicates whether view state is
maintained across page requests
Explicit For VB language, tells the compiler to use option explicit
mode
Inherits The class from which the control page inherits.

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67
Language The language for code and script.
Src The filename for the code-behind class.
Strict For VB language, tells the compiler to use the option strict
mode.
TheImplementsDirective
The Implement directive indicates that the web page, master page or user control
page must implement the specified .Net framework interface.
The basic syntax for implements directive is:
<%@ Implements Interface="interface_name" %>
TheImportDirective
The Import directive imports a namespace into a web page, user control page of
application. If the Import directive is specified in the global.asax file, then it is applied
to the entire application. If it is in a page of user control page, then it is applied to
that page or control.
The basic syntax for import directive is:
<%@ namespace="System.Drawing" %>
TheMasterDirective
The Master directive specifies a page file as being the mater page.
The basic syntax of MasterPage directive is:
<%@ MasterPage Language="C#" AutoEventWireup="true"
CodeFile="SiteMater.master.cs" Inherits="SiteMaster" %>
TheMasterTypeDirective
The MasterType directive assigns a class name to the Master property of a page, to
make it strongly typed.
The basic syntax of MasterType directive is:

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<%@ MasterType attribute="value"[attribute="value" ...] %>
TheOutputCacheDirective
The OutputCache directive controls the output caching policies of a web page or a
user control.
The basic syntax of OutputCache directive is:
<%@ OutputCache Duration="15" VaryByParam="None" %>
ThePageDirective
The Page directive defines the attributes specific to the page file for the page parser
and the compiler.
The basic syntax of Page directive is:
CodeFile="Default.aspx.cs" Inherits="_Default" Trace="true" %>
The attributes of the Page directive are:
AutoEventWireup The Boolean value that enables or disables page events that
are being automatically bound to methods; for example,
Page_Load.
Buffer The Boolean value that enables or disables HTTP response
buffering.
ClassName The class name for the page.
ClientTarget The browser for which the server controls should render
content.
CodeFile The name of the code behind file.
Debug The Boolean value that enables or disables compilation with
debug symbols.

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Description The text description of the page, ignored by the parser.
EnableSessionState It enables, disables, or makes session state read-only.
EnableViewState The Boolean value that enables or disables view state across
page requests.
ErrorPage URL for redirection if an unhandled page exception occurs.
Inherits The name of the code behind or other class.
Language The programming language for code.
Src The file name of the code behind class.
Trace It enables or disables tracing.
TraceMode It indicates how trace messages are displayed, and sorted by
time or category.
Transaction It indicates if transactions are supported.
ValidateRequest The Boolean value that indicates whether all input data is
validated against a hardcoded list of values.
ThePreviousPageTypeDirective
The PreviousPageType directive assigns a class to a page, so that the page is strongly
typed.
The basic syntax for a sample PreviousPagetype directive is:
<%@ PreviousPageType attribute="value"[attribute="value" ...] %>
TheReferenceDirective
The Reference directive indicates that another page or user control should be
compiled and linked to the current page.
The basic syntax of Reference directive is:

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<%@ Reference Page ="somepage.aspx" %>
TheRegisterDirective
The Register derivative is used for registering the custom server controls and user
controls.
The basic syntax of Register directive is:
<%@ Register Src="~/footer.ascx" TagName="footer"
TagPrefix="Tfooter" %>

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71
Hyper Text Transfer Protocol (HTTP) is a stateless protocol. When the client
disconnects from the server, the ASP.NET engine discards the page objects. This way,
each web application can scale up to serve numerous requests simultaneously
without running out of server memory.
However, there needs to be some technique to store the information between
requests and to retrieve it when required. This information i.e., the current value of
all the controls and variables for the current user in the current session is called the
State.
ASP.NET manages four types of states:
 View State
 Control State
 Session State
 Application State
View State
The view state is the state of the page and all its controls. It is automatically
maintained across posts by ASP.NET framework.
When a page is sent back to the client, the changes in the properties of the page and
its controls are determined, and stored in the value of a hidden input field named
_VIEWSTATE. When the page is again posted back, the _VIEWSTATE field is sent to
the server with the HTTP request.
The view state could be enabled or disabled for:
 The entire application by setting the EnableViewState property in the
<pages> section of web.config file.
 A page by setting the EnableViewState attribute of the Page directive, as
<%@ Page Language="C#" EnableViewState="false" %>
 A control by setting the Control.EnableViewState property.
It is implemented using a view state object defined by the StateBag class which
defines a collection of view state items. The state bag is a data structure containing
attribute-value pairs, stored as strings associated with objects.
The StateBag class has the following properties:
Properties Description
12. MANAGING STATE

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72
Item(name) The value of the view state item with the specified name.
This is the default property of the StateBag class.
Count The number of items in the view state collection.
Keys Collection of keys for all the items in the collection.
Values Collection of values for all the items in the collection.
The StateBag class has the following methods:
Methods Description
Add(name, value) Adds an item to the view state collection and existing item
is updated.
Clear Removes all the items from the collection.
Equals(Object) Determines whether the specified object is equal to the
current object.
Finalize Allows it to free resources and perform other cleanup
operations.
GetEnumerator Returns an enumerator that iterates over all the key/value
pairs of the StateItem objects stored in the StateBag
object.
GetType Gets the type of the current instance.
IsItemDirty Checks a StateItem object stored in the StateBag object
to evaluate whether it has been modified.
Remove(name) Removes the specified item.
SetDirty Sets the state of the StateBag object as well as the Dirty
property of each of the StateItem objects contained by it.
SetItemDirty Sets the Dirty property for the specified StateItem object
in the StateBag object.

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ToString Returns a string representing the state bag object.
Example
The following example demonstrates the concept of storing view state. Let us keep a
counter, which is incremented each time the page is posted back by clicking a button
on the page. A label control shows the value in the counter.
The markup file code is as follows:
<%@ Page Language="C#"
AutoEventWireup="true"
Inherits="statedemo._Default" %>
</head>
<body>
<div>
<h3>View State demo</h3>
Page Counter:
<asp:Label ID="lblCounter" runat="server" />
<asp:Button ID="btnIncrement" runat="server"
Text="Add Count"
onclick="btnIncrement_Click" />
</div>

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</form>
</body>
</html>
The code behind file for the example is shown here:
{
public int counter
{
get
{
if (ViewState["pcounter"] != null)
{
return ((int)ViewState["pcounter"]);
}
else
{
return 0;
}
}
set
{
ViewState["pcounter"] = value;
}
}
{
lblCounter.Text = counter.ToString();

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counter++;
}
}
It would produce the following result:
ControlState
Control state cannot be modified, accessed directly, or disabled.
SessionState
When a user connects to an ASP.NET website, a new session object is created. When
session state is turned on, a new session state object is created for each new request.
This session state object becomes part of the context and it is available through the
page.
Session state is generally used for storing application data such as inventory, supplier
list, customer record, or shopping cart. It can also keep information about the user
and his preferences, and keep the track of pending operations.
Sessions are identified and tracked with a 120-bit SessionID, which is passed from
client to server and back as cookie or a modified URL. The SessionID is globally
unique and random.
The session state object is created from the HttpSessionState class, which defines a
collection of session state items.
The HttpSessionState class has the following properties:
SessionID The unique session identifier.
Item(name) The value of the session state item with the specified name.
This is the default property of the HttpSessionState class.
Count The number of items in the session state collection.

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76
TimeOut Gets and sets the amount of time, in minutes, allowed
between requests before the session-state provider
terminates the session.
The HttpSessionState class has the following methods:
Methods Description
Add(name, value) Adds an item to the session state collection.
Clear Removes all the items from session state collection.
Remove(name) Removes the specified item from the session state
collection.
RemoveAll Removes all keys and values from the session-state
collection.
RemoveAt Deletes an item at a specified index from the session-state
collection.
The session state object is a name-value pair to store and retrieve some information
from the session state object. You could use the following code for the same:
void StoreSessionInfo()
{
String fromuser = TextBox1.Text;
Session["fromuser"] = fromuser;
}
void RetrieveSessionInfo()
{
String fromuser = Session["fromuser"];
Label1.Text = fromuser;
}

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The above code stores only strings in the Session dictionary object, however, it can
store all the primitive data types and arrays composed of primitive data types, as
well as the DataSet, DataTable, HashTable, and Image objects, as well as any user-
defined class that inherits from the ISerializable object.
Example
The following example demonstrates the concept of storing session state. There are
two buttons on the page, a text box to enter string and a label to display the text
stored from last session.
The mark up file code is as follows:
CodeFile="Default.aspx.cs"
Inherits="_Default" %>
</head>
<body>
<div>
     
<table style="width: 568px; height: 103px">
<tr>
<td style="width: 209px">
<asp:Label ID="lblstr" runat="server"
Text="Enter a String" style="width:94px">

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</asp:Label>
</td>
<asp:TextBox ID="txtstr" runat="server" style="width:227px">
</asp:TextBox>
</td>
</tr>
<tr>
<td style="width: 209px"></td>
<td style="width: 317px"></td>
</tr>
<tr>
<asp:Button ID="btnnrm" runat="server"
Text="No action button" style="width:128px" />
</td>
<asp:Button ID="btnstr" runat="server"
OnClick="btnstr_Click" Text="Submit the String" />
</td>
</tr>
<tr>
</td>
</td>
</tr>
<tr>

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<asp:Label ID="lblsession" runat="server"
style="width:231px">
</asp:Label>
</td>
</td>
</tr>
<tr>
<asp:Label ID="lblshstr" runat="server">
</asp:Label>
</td>
</td>
</tr>
</table>
</div>
</form>
</body>
</html>
It should look like the following in design view:

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The code behind file is given here:
{
String mystr;
{
this.lblshstr.Text = this.mystr;
this.lblsession.Text = (String)this.Session["str"];
}
protected void btnstr_Click(object sender, EventArgs e)
{
this.mystr = this.txtstr.Text;
this.Session["str"] = this.txtstr.Text;
this.lblshstr.Text = this.mystr;
this.lblsession.Text = (String)this.Session["str"];
}
}
Execute the file and observe how it works:

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ApplicationState
TheASP.NET application is the collection of all web pages, code and other files within
a single virtual directory on a web server. When information is stored in application
state, it is available to all the users.
To provide for the use of application state, ASP.NET creates an application state
object for each application from the HTTPApplicationState class and stores this object
in server memory. This object is represented by class file global.asax.
Application State is mostly used to store hit counters and other statistical data, global
application data like tax rate, discount rate etc. and to keep the track of users visiting
the site.
The HttpApplicationState class has the following properties:
Item(name) The value of the application state item with the specified
name. This is the default property of the
HttpApplicationState class.
Count The number of items in the application state collection.
The HttpApplicationState class has the following methods:
Methods Description
Add(name, value) Adds an item to the application state collection.
Clear Removes all the items from the application state collection.

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Remove(name) Removes the specified item from the application state
collection.
RemoveAll Removes all objects from an HttpApplicationState collection.
RemoveAt Removes an HttpApplicationState object from a collection
by index.
Lock() Locks the application state collection so only the current
user can access it.
Unlock() Unlocks the application state collection so all the users can
access it.
Application state data is generally maintained by writing handlers for the events:
 Application_Start
 Application_End
 Application_Error
 Session_Start
 Session_End
The following code snippet shows the basic syntax for storing application state
information:
Void Application_Start(object sender, EventArgs e)
{
Application["startMessage"] = "The application has started.";
}
Void Application_End(object sender, EventArgs e)
{
Application["endtMessage"] = "The application has ended.";

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ASP.NET validation controls validate the user input data to ensure that useless,
unauthenticated, or contradictory data don’t get stored.
ASP.NET provides the following validation controls:
 RequiredFieldValidator
 RangeValidator
 CompareValidator
 RegularExpressionValidator
 CustomValidator
 ValidationSummary
BaseValidatorClass
The validation control classes are inherited from the BaseValidator class hence they
inherit its properties and methods. Therefore, it would help to take a look at the
properties and the methods of this base class, which are common for all the validation
controls:
Members Description
ControlToValidate Indicates the input control to validate.
Display Indicates how the error message is shown.
EnableClientScript Indicates whether client side validation will take.
Enabled Enables or disables the validator.
ErrorMessage Indicates error string.
Text Error text to be shown if validation fails.
IsValid Indicates whether the value of the control is valid.
SetFocusOnError It indicates whether in case of an invalid control, the focus
should switch to the related input control.
13. VALIDATORS

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ValidationGroup The logical group of multiple validators, where this control
belongs.
Validate() This method revalidates the control and updates the IsValid
property.
RequiredFieldValidatorControl
The RequiredFieldValidator control ensures that the required field is not empty. It is
generally tied to a text box to force input into the text box.
The syntax of the control is as given:
<asp:RequiredFieldValidator ID="rfvcandidate"
runat="server" ControlToValidate ="ddlcandidate"
ErrorMessage="Please choose a candidate"
InitialValue="Please choose a candidate">
</asp:RequiredFieldValidator>
RangeValidatorControl
The RangeValidator control verifies that the input value falls within a predetermined
range.
It has three specific properties:
Type It defines the type of the data. The available values are:
Currency, Date, Double, Integer, and String.
MinimumValue It specifies the minimum value of the range.
MaximumValue It specifies the maximum value of the range.
<asp:RangeValidator ID="rvclass"
runat="server"
ControlToValidate="txtclass"

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ErrorMessage="Enter your class (6 - 12)"
MaximumValue="12"
MinimumValue="6" Type="Integer">
</asp:RangeValidator>
CompareValidatorControl
The CompareValidator control compares a value in one control with a fixed value or
a value in another control.
It has the following specific properties:
Type It specifies the data type.
ControlToCompare It specifies the value of the input control to compare with.
ValueToCompare It specifies the constant value to compare with.
Operator It specifies the comparison operator, the available values
are: Equal, NotEqual, GreaterThan, GreaterThanEqual,
LessThan, LessThanEqual, and DataTypeCheck.
The basic syntax of the control is as follows:
<asp:CompareValidator ID="CompareValidator1"
runat="server"
ErrorMessage="CompareValidator">
</asp:CompareValidator>
RegularExpressionValidator
The RegularExpressionValidator control allows validating the input text by matching
against a pattern of a regular expression. The regular expression is set in the
ValidationExpression property.
The following table summarizes the commonly used syntax constructs for regular
expressions:

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Character Escapes Description
b Matches a backspace
t Matches a tab
r Matches a carriage return
v Matches a vertical tab
f Matches a form feed
n Matches a new line
Escape character
Apart from single character match, a class of characters could be specified that can
be matched, called the metacharacters.
Metacharacters Description
. Matches any character except n.
[abcd] Matches any character in the set.
[^abcd] Excludes any character in the set.
[2-7a-mA-M] Matches any character specified in the range.
w Matches any alphanumeric character and underscore.
W Matches any non-word character.
s Matches whitespace characters like, space, tab, new line
etc.
S Matches any non-whitespace character.

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d Matches any decimal character.
D Matches any non-decimal character.
Quantifiers could be added to specify number of times a character could appear.
Quantifier Description
* Zero or more matches
+ One or more matches
? Zero or one matches
{N} N matches
{N,} N or more matches
{N,M} Between N and M matches
<asp:RegularExpressionValidator ID="string"
runat="server"
ErrorMessage="string"
ValidationExpression="string"
ValidationGroup="string">
</asp:RegularExpressionValidator>
CustomValidator
The CustomValidator control allows writing application specific custom validation
routines for both the client side and the server side validation.
The client side validation is accomplished through the ClientValidationFunction
property. The client side validation routine should be written in a scripting language,
such as JavaScript or VBScript, which the browser can understand.

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The server side validation routine must be called from the control’s ServerValidate
event handler. The server side validation routine should be written in any .Net
language, like C# or VB.Net.
The basic syntax for the control is as given:
<asp:CustomValidator ID="CustomValidator1"
runat="server"
ClientValidationFunction=.cvf_func.
ErrorMessage="CustomValidator">
</asp:CustomValidator>
ValidationSummary
The ValidationSummary control does not perform any validation but shows a
summary of all errors in the page. The summary displays the values of the
ErrorMessage property of all validation controls that failed validation.
The following two mutually inclusive properties list out the error message:
 ShowSummary: shows the error messages in specified format.
 ShowMessageBox: shows the error messages in a separate window.
The syntax for the control is as given:
<asp:ValidationSummary ID="ValidationSummary1"
runat="server"
DisplayMode = "BulletList"
ShowSummary = "true"
HeaderText="Errors:" />
ValidationGroups
Complex pages have different groups of information provided in different panels. In
such situation, a need might arise for performing validation separately for separate
group. This kind of situation is handled using validation groups.
To create a validation group, you should put the input controls and the validation
controls into the same logical group by setting their ValidationGroup property.
Example

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The following example describes a form to be filled up by all the students of a school,
divided into four houses, for electing the school president. Here, we use the validation
controls to validate the user input.
This is the form in design view:
<tr>
<td class="style1" colspan="3" align="center">
<asp:Label ID="lblmsg"
Text="President Election Form : Choose your president"
runat="server" />
</td>
</tr>
<tr>

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<td class="style3">
Candidate:
</td>
<td class="style2">
<asp:DropDownList ID="ddlcandidate" runat="server" style="width:239px">
<asp:ListItem>Please Choose a Candidate</asp:ListItem>
<asp:ListItem>M H Kabir</asp:ListItem>
<asp:ListItem>Steve Taylor</asp:ListItem>
<asp:ListItem>John Abraham</asp:ListItem>
<asp:ListItem>Venus Williams</asp:ListItem>
</asp:DropDownList>
</td>
<td>
<asp:RequiredFieldValidator ID="rfvcandidate"
runat="server" ControlToValidate ="ddlcandidate"
ErrorMessage="Please choose a candidate"
InitialValue="Please choose a candidate">
</td>
</tr>
<tr>
<td class="style3">
House:</td>
<td class="style2">
<asp:RadioButtonList ID="rblhouse"
runat="server"
RepeatLayout="Flow">
<asp:ListItem>Red</asp:ListItem>

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<asp:ListItem>Blue</asp:ListItem>
<asp:ListItem>Yellow</asp:ListItem>
<asp:ListItem>Green</asp:ListItem>
</asp:RadioButtonList>
</td>
<td>
<asp:RequiredFieldValidator ID="rfvhouse"
runat="server"
ControlToValidate="rblhouse"
ErrorMessage="Enter your house name">
<br />
</td>
</tr>
<tr>
<td class="style3">
Class:</td>
<td class="style2">
<asp:TextBox ID="txtclass" runat="server"></asp:TextBox>
</td>
<td>
<asp:RangeValidator ID="rvclass"
runat="server" ControlToValidate="txtclass"
ErrorMessage="Enter your class (6 - 12)" MaximumValue="12"
MinimumValue="6" Type="Integer">
</asp:RangeValidator>
</td>
</tr>

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<tr>
<td class="style3">
Email:</td>
<td class="style2">
<asp:TextBox ID="txtemail" runat="server" style="width:250px">
</asp:TextBox>
</td>
<td>
<asp:RegularExpressionValidator ID="remail"
runat="server"
ControlToValidate="txtemail" ErrorMessage="Enter your email"
ValidationExpression="w+([-+.']w+)*@w+([-.]w+)*.w+([-.]w+)*">
</asp:RegularExpressionValidator>
</td>
</tr>
<tr>
<td class="style3" align="center" colspan="3">
<asp:Button ID="btnsubmit" runat="server" onclick="btnsubmit_Click"
style="text-align: center" Text="Submit" style="width:140px" />
</td>
</tr>
</table>
<asp:ValidationSummary ID="ValidationSummary1"
runat="server"
DisplayMode ="BulletList"
ShowSummary ="true"
HeaderText="Errors:" />
</form>

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The code behind the submit button:
protected void btnsubmit_Click(object sender, EventArgs e)
{
if (Page.IsValid)
{
lblmsg.Text = "Thank You";
}
else
{
lblmsg.Text = "Fill up all the fields";
}
}

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ASP.NET allows the following sources of data to be accessed and used:
 Databases (e.g., Access, SQL Server, Oracle, MySQL)
 XML documents
 Business Objects
 Flat files
ASP.NET hides the complex processes of data access and provides much higher level
of classes and objects through which data is accessed easily. These classes hide all
complex coding for connection, data retrieving, data querying, and data
manipulation.
ADO.NET is the technology that provides the bridge between various ASP.NET control
objects and the backend data source. In this tutorial, we will look at data access and
working with the data in brief.
RetrievingandDisplayingData
It takes two types of data controls to retrieve and display data in ASP.NET:
 A data source control - It manages the connection to the data, selection of
data, and other jobs such as paging and caching of data etc.
 A data view control - It binds and displays the data and allows data
manipulation.
We will discuss the data binding and data source controls in detail later. In this
section, we will use a SqlDataSource control to access data and a GridView control to
display and manipulate data in this chapter.
We will also use an Access database, which contains the details about .Net books
available in the market. Name of our database is ASPDotNetStepByStep.mdb and we
will use the data table DotNetReferences.
The table has the following columns: ID, Title, AuthorFirstName, AuthorLastName,
Topic, and Publisher.
Here is a snapshot of the data table:
14. DATABASE ACCESS

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Let us directly move to action, take the following steps:
(1) Create a web site and add a SqlDataSourceControl on the web form.
(2) Click on the Configure Data Source option.

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(3) Click on the New Connection button to establish connection with a database.
(4) Once the connection is set up, you may save it for further use. At the next step,
you are asked to configure the select statement:
(5) Select the columns and click next to complete the steps. Observe the WHERE…,
ORDER BY…, and the Advanced… buttons. These buttons allow you to provide the

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where clause, order by clause, and specify the insert, update, and delete commands
of SQL respectively. This way, you can manipulate the data.
(6) Add a GridView control on the form. Choose the data source and format the
control using AutoFormat option.
(7) After this, the formatted GridView control displays the column headings, and the
application is ready to execute.

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(8) Finally execute the application.
CodeBehind="dataaccess.aspx.cs"
Inherits="datacaching.WebForm1" %>
</head>
<body>
<div>
<asp:SqlDataSource ID="SqlDataSource1"

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runat="server"
ConnectionString=
"<%$ ConnectionStrings:ASPDotNetStepByStepConnectionString%>"
ProviderName=
"<%$ ConnectionStrings:
ASPDotNetStepByStepConnectionString.ProviderName %>"
SelectCommand="SELECT [Title], [AuthorLastName],
[AuthorFirstName], [Topic]
FROM [DotNetReferences]">
</asp:SqlDataSource>
<asp:GridView ID="GridView1"
runat="server"
AutoGenerateColumns="False"
CellPadding="4"
DataSourceID="SqlDataSource1"
ForeColor="#333333"
GridLines="None">
<RowStyle BackColor="#F7F6F3" ForeColor="#333333" />
<Columns>
<asp:BoundField DataField="Title" HeaderText="Title"
SortExpression="Title" />
<asp:BoundField DataField="AuthorLastName"
HeaderText="AuthorLastName"
SortExpression="AuthorLastName" />
<asp:BoundField DataField="AuthorFirstName"
HeaderText="AuthorFirstName"
SortExpression="AuthorFirstName" />
<asp:BoundField DataField="Topic"

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HeaderText="Topic" SortExpression="Topic" />
</Columns>
<FooterStyle BackColor="#5D7B9D"
Font-Bold="True" ForeColor="White" />
<PagerStyle BackColor="#284775"
ForeColor="White" HorizontalAlign="Center" />
<SelectedRowStyle BackColor="#E2DED6"
Font-Bold="True" ForeColor="#333333" />
<HeaderStyle BackColor="#5D7B9D" Font-Bold="True"
ForeColor="White" />
<EditRowStyle BackColor="#999999" />
<AlternatingRowStyle BackColor="White" ForeColor="#284775" />
</asp:GridView>
</div>
</form>
</body>
</html>

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The ADO.NET provides a bridge between the front end controls and the back end
database. The ADO.NET objects encapsulate all the data access operations and the
controls interact with these objects to display data, thus hiding the details of
movement of data.
The following figure shows the ADO.NET objects at a glance:
TheDataSetClass
The dataset represents a subset of the database. It does not have a continuous
connection to the database. To update the database a reconnection is required. The
DataSet contains DataTable objects and DataRelation objects. The DataRelation
objects represent the relationship between two tables.
Following table shows some important properties of the DataSet class:
15. ADO.NET

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CaseSensitive Indicates whether string comparisons within the data tables
are case-sensitive.
Container Gets the container for the component.
DataSetName Gets or sets the name of the current data set.
DefaultViewManager Returns a view of data in the data set.
DesignMode Indicates whether the component is currently in design
mode.
EnforceConstraints Indicates whether constraint rules are followed when
attempting any update operation.
Events Gets the list of event handlers that are attached to this
component.
ExtendedProperties Gets the collection of customized user information
associated with the DataSet.
HasErrors Indicates if there are any errors.
IsInitialized Indicates whether the DataSet is initialized.
Locale Gets or sets the locale information used to compare strings
within the table.
Namespace Gets or sets the namespace of the DataSet.
Prefix Gets or sets an XML prefix that aliases the namespace of
the DataSet.
Relations Returns the collection of DataRelation objects.
Tables Returns the collection of DataTable objects.

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The following table shows some important methods of the DataSet class:
Methods Description
AcceptChanges Accepts all changes made since the
DataSet was loaded or this method
was called.
BeginInit Begins the initialization of the
DataSet. The initialization occurs at
run time.
Clear Clears data.
Clone Copies the structure of the DataSet,
including all DataTable schemas,
relations, and constraints. Does not
copy any data.
Copy Copies both structure and data.
CreateDataReader() Returns a DataTableReader with one
result set per DataTable, in the
same sequence as the tables appear
in the Tables collection.
CreateDataReader(DataTable[]) Returns a DataTableReader with one
result set per DataTable.
EndInit Ends the initialization of the data
set.
Equals(Object) Determines whether the specified
Object is equal to the current
Object.
Finalize Free resources and perform other
cleanups.
GetChanges Returns a copy of the DataSet with
all changes made since it was loaded
or the AcceptChanges method was
called.

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GetChanges(DataRowState) Gets a copy of DataSet with all
changes made since it was loaded or
the AcceptChanges method was
called, filtered by DataRowState.
GetDataSetSchema Gets a copy of XmlSchemaSet for
the DataSet.
GetObjectData Populates a serialization information
object with the data needed to
serialize the DataSet.
GetType Gets the type of the current
instance.
GetXML Returns the XML representation of
the data.
GetXMLSchema Returns the XSD schema for the
XML representation of the data.
HasChanges() Gets a value indicating whether the
DataSet has changes, including
new, deleted, or modified rows.
HasChanges(DataRowState) Gets a value indicating whether the
DataSet has changes, including
new, deleted, or modified rows,
filtered by DataRowState.
IsBinarySerialized Inspects the format of the serialized
representation of the DataSet.
Load(IDataReader, LoadOption, DataTable[]) Fills a DataSet with values from a
data source using the supplied
IDataReader, using an array of
DataTable instances to supply the
schema and namespace
information.
Load(IDataReader, LoadOption, String[]) Fills a DataSet with values from a
data source using the supplied
IDataReader, using an array of

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strings to supply the names for the
tables within the DataSet.
Merge() Merges the data with data from
another DataSet. This method has
different overloaded forms.
ReadXML() Reads an XML schema and data into
the DataSet. This method has
ReadXMLSchema(0) Reads an XML schema into the
DataSet. This method has different
overloaded forms.
RejectChanges Rolls back all changes made since
the last call to AcceptChanges.
WriteXML() Writes an XML schema and data
from the DataSet. This method has
WriteXMLSchema() Writes the structure of the DataSet
as an XML schema. This method has
TheDataTableClass
The DataTable class represents the tables in the database. It has the following
important properties; most of these properties are read only properties except the
PrimaryKey property:
ChildRelations Returns the collection of child relationship.
Columns Returns the Columns collection.
Constraints Returns the Constraints collection.
DataSet Returns the parent DataSet.

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DefaultView Returns a view of the table.
ParentRelations Returns the ParentRelations collection.
PrimaryKey Gets or sets an array of columns as the primary key for the
table.
Rows Returns the Rows collection.
The following table shows some important methods of the DataTable class:
Methods Description
AcceptChanges Commits all changes since the last AcceptChanges.
Clear Clears all data from the table.
GetChanges Returns a copy of the DataTable with all changes made since
the AcceptChanges method was called.
GetErrors Returns an array of rows with errors.
ImportRows Copies a new row into the table.
LoadDataRow Finds and updates a specific row, or creates a new one, if
not found any.
Merge Merges the table with another DataTable.
NewRow Creates a new DataRow.
RejectChanges Rolls back all changes made since the last call to
AcceptChanges.
Reset Resets the table to its original state.
Select Returns an array of DataRow objects.

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TheDataRow Class
The DataRow object represents a row in a table. It has the following important
properties:
HasErrors Indicates if there are any errors.
Items Gets or sets the data stored in a specific column.
ItemArrays Gets or sets all the values for the row.
Table Returns the parent table.
The following table shows some important methods of the DataRow class:
Methods Description
AcceptChanges Accepts all changes made since this method was called.
BeginEdit Begins edit operation.
CancelEdit Cancels edit operation.
Delete Deletes the DataRow.
EndEdit Ends the edit operation.
GetChildRows Gets the child rows of this row.
GetParentRow Gets the parent row.
GetParentRows Gets parent rows of DataRow object.
RejectChanges Rolls back all changes made since the last call to
AcceptChanges.

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TheDataAdapterObject
The DataAdapter object acts as a mediator between the DataSet object and the
database. This helps the Dataset to contain data from multiple databases or other
data source.
TheDataReaderObject
The DataReader object is an alternative to the DataSet and DataAdapter combination.
This object provides a connection oriented access to the data records in the database.
These objects are suitable for read-only access, such as populating a list and then
breaking the connection.
DbCommandandDbConnectionObjects
The DbConnection object represents a connection to the data source. The connection
could be shared among different command objects.
The DbCommand object represents the command or a stored procedure sent to the
database from retrieving or manipulating data.
Example
So far, we have used tables and databases already existing in our computer. In this
example, we will create a table, add column, rows and data into it and display the
table using a GridView object.
The source file code is as given:
Inherits="createdatabase._Default" %>
</head>

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<body>
<div>
<asp:GridView ID="GridView1" runat="server">
</asp:GridView>
</div>
</form>
</body>
</html>
The code behind file is as given:
namespace createdatabase
{
{
{
if (!IsPostBack)
{
DataSet ds = CreateDataSet();
GridView1.DataSource = ds.Tables["Student"];
GridView1.DataBind();
}
}
private DataSet CreateDataSet()
{
//creating a DataSet object for tables

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110
DataSet dataset = new DataSet();
// creating the student table
DataTable Students = CreateStudentTable();
dataset.Tables.Add(Students);
return dataset;
}
private DataTable CreateStudentTable()
{
DataTable Students = new DataTable("Student");
// adding columns
AddNewColumn(Students, "System.Int32", "StudentID");
AddNewColumn(Students, "System.String", "StudentName");
AddNewColumn(Students, "System.String", "StudentCity");
// adding rows
AddNewRow(Students, 1, "M H Kabir", "Kolkata");
AddNewRow(Students, 1, "Shreya Sharma", "Delhi");
AddNewRow(Students, 1, "Rini Mukherjee", "Hyderabad");
AddNewRow(Students, 1, "Sunil Dubey", "Bikaner");
AddNewRow(Students, 1, "Rajat Mishra", "Patna");
return Students;
}
private void AddNewColumn(DataTable table,
string columnType,

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string columnName)
{
DataColumn column = table.Columns.Add(columnName,
Type.GetType(columnType));
}
//adding data into the table
private void AddNewRow(DataTable table, int id,
string name, string city)
{
DataRow newrow = table.NewRow();
newrow["StudentID"] = id;
newrow["StudentName"] = name;
newrow["StudentCity"] = city;
table.Rows.Add(newrow);
}
}
}
When you execute the program, observe the following:
 The application first creates a data set and binds it with the grid view control
using the DataBind() method of the GridView control.
 The Createdataset() method is a user defined function, which creates a new
DataSet object and then calls another user defined method
CreateStudentTable() to create the table and add it to the Tables collection of
the data set.
 The CreateStudentTable() method calls the user defined methods
AddNewColumn() and AddNewRow() to create the columns and rows of the
table as well as to add data to the rows.
When the page is executed, it returns the rows of the table as shown:

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ASP.NET has two controls that allow users to upload files to the web server. Once the
server receives the posted file data, the application can save it, check it, or ignore it.
The following controls allow the file uploading:
 HtmlInputFile - an HTML server control
 FileUpload - and ASP.NET web control
Both controls allow file uploading, but the FileUpload control automatically sets the
encoding of the form, whereas the HtmlInputFile does not do so.
In this tutorial, we use the FileUpload control. The FileUpload control allows the user
to browse for and select the file to be uploaded, providing a browse button and a text
box for entering the filename.
Once the user has entered the filename in the text box by typing the name or
browsing, the SaveAs method of the FileUpload control can be called to save the file
to the disk.
The basic syntax of FileUpload is:
<asp:FileUpload ID= "Uploader" runat = "server" />
The FileUpload class is derived from the WebControl class, and inherits all its
members. Apart from those, the FileUpload class has the following read-only
properties:
FileBytes Returns an array of the bytes in a file to be uploaded.
FileContent Returns the stream object pointing to the file to be uploaded.
FileName Returns the name of the file to be uploaded.
HasFile Specifies whether the control has a file to upload.
PostedFile Returns a reference to the uploaded file.
The posted file is encapsulated in an object of type HttpPostedFile, which could be
accessed through the PostedFile property of the FileUpload class.
The HttpPostedFile class has the following frequently used properties:
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ContentLength Returns the size of the uploaded file in bytes.
ContentType Returns the MIME type of the uploaded file.
FileName Returns the full filename.
InputStream Returns a stream object pointing to the uploaded file.
Example
The following example demonstrates the FileUpload control and its properties. The
form has a FileUpload control along with a save button and a label control for
displaying the file name, file type, and file length.
In the design view, the form looks as follows:
<body>
<div>
<h3> File Upload:</h3>
<br />
<asp:FileUpload ID="FileUpload1" runat="server" />
<br /><br />

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<asp:Button ID="btnsave" runat="server"
onclick="btnsave_Click" Text="Save"
style="width:85px" />
<br /><br />
<asp:Label ID="lblmessage" runat="server" />
</div>
</form>
</body>
The code behind the save button is as given:
protected void btnsave_Click(object sender, EventArgs e)
{
StringBuilder sb = new StringBuilder();
if (FileUpload1.HasFile)
{
try
{
sb.AppendFormat(" Uploading file: {0}", FileUpload1.FileName);
//saving the file
FileUpload1.SaveAs("<c:SaveDirectory>" + FileUpload1.FileName);
//Showing the file information
sb.AppendFormat("<br/> Save As: {0}", FileUpload1.PostedFile.FileName);
sb.AppendFormat("<br/> File type: {0}", FileUpload1.PostedFile.ContentType);
sb.AppendFormat("<br/> File length: {0}",
FileUpload1.PostedFile.ContentLength);
sb.AppendFormat("<br/> File name: {0}", FileUpload1.PostedFile.FileName);
}
catch (Exception ex)
{

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sb.Append("<br/> Error <br/>");
sb.AppendFormat("Unable to save file <br/> {0}", ex.Message);
}
}
else
{
lblmessage.Text = sb.ToString();
}
}
Note the following:
 The StringBuilder class is derived from System.IO namespace, so it needs to
be included.
 The try and catch blocks are used for catching errors, and display the error
message.

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The AdRotator control randomly selects banner graphics from a list, which is specified
in an external XML schedule file. This external XML schedule file is called the
advertisement file.
The AdRotator control allows you to specify the advertisement file and the type of
window that the link should follow in the AdvertisementFile and the Target property
respectively.
The basic syntax of adding an AdRotator is as follows:
<asp:AdRotator runat = "server"
AdvertisementFile = "adfile.xml"
Target = "_blank" />
Before going into the details of the AdRotator control and its properties, let us look
into the construction of the advertisement file.
TheAdvertisementFile
The advertisement file is an XML file, which contains the information about the
advertisements to be displayed.
Extensible Markup Language (XML) is a W3C standard for text document markup. It
is a text-based markup language that enables you to store data in a structured format
by using meaningful tags. The term 'extensible' implies that you can extend your
ability to describe a document by defining meaningful tags for the application.
XML is not a language in itself like HTML, but a set of rules for creating new markup
languages. It is a meta-markup language. It allows developers to create custom tag
sets for special uses. It structures, stores, and transports the information.
Following is an example of XML file:
<BOOK>
<NAME> Learn XML </NAME>
<AUTHOR> Samuel Peterson </AUTHOR>
<PUBLISHER> NSS Publications </PUBLISHER>
<PRICE> $30.00</PRICE>
</BOOK>
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Like all XML files, the advertisement file needs to be a structured text file with well-
defined tags delineating the data. There are the following standard XML elements
that are commonly used in the advertisement file:
Element Description
Advertisements Encloses the advertisement file.
Ad Delineates separate ad.
ImageUrl The path of image that will be displayed.
NavigateUrl The link that will be followed when the user clicks the ad.
AlternateText The text that will be displayed instead of the picture if it
cannot be displayed.
Keyword Keyword identifying a group of advertisements. This is used
for filtering.
Impressions The number indicating how often an advertisement will
appear.
Height Height of the image to be displayed.
Width Width of the image to be displayed.
Apart from these tags, customs tags with custom attributes could also be included.
The following code illustrates an advertisement file ads.xml:
<Advertisements>
<Ad>
<ImageUrl>rose1.jpg</ImageUrl>
<NavigateUrl>http://www.1800flowers.com</NavigateUrl>
<AlternateText>
Order flowers, roses, gifts and more
</AlternateText>
<Impressions>20</Impressions>

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<Keyword>flowers</Keyword>
</Ad>
<Ad>
<NavigateUrl>http://www.babybouquets.com.au</NavigateUrl>
<AlternateText>Order roses and flowers</AlternateText>
<Keyword>gifts</Keyword>
</Ad>
<Ad>
<NavigateUrl>http://www.flowers2moscow.com</NavigateUrl>
<AlternateText>Send flowers to Russia</AlternateText>
<Keyword>russia</Keyword>
</Ad>
<Ad>
<NavigateUrl>http://www.edibleblooms.com</NavigateUrl>
<AlternateText>Edible Blooms</AlternateText>
<Keyword>gifts</Keyword>
</Ad>
</Advertisements>

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PropertiesandEventsoftheAdRotatorClass
The AdRotator class is derived from the WebControl class and inherits its properties.
Apart from those, the AdRotator class has the following properties:
AdvertisementFile The path to the advertisement file.
AlternateTextFeild The element name of the field where alternate text is
provided. The default value is AlternateText.
DataMember The name of the specific list of data to be bound when
advertisement file is not used.
DataSource Control from where it would retrieve data.
DataSourceID Id of the control from where it would retrieve data.
Font Specifies the font properties associated with the
advertisement banner control.
ImageUrlField The element name of the field where the URL for the image
is provided. The default value is ImageUrl.
KeywordFilter For displaying the keyword based ads only.
NavigateUrlField The element name of the field where the URL to navigate to
is provided. The default value is NavigateUrl.
Target The browser window or frame that displays the content of
the page linked.
UniqueID Obtains the unique, hierarchically qualified identifier for the
AdRotator control.

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Following are the important events of the AdRotator class:
Events Description
AdCreated It is raised once per round trip to the server after creation
of the control, but before the page is rendered
DataBinding Occurs when the server control binds to a data source.
DataBound Occurs after the server control binds to a data source.
Disposed Occurs when a server control is released from memory,
which is the last stage of the server control lifecycle when
an ASP.NET page is requested.
Init Occurs when the server control is initialized, which is the
first step in its lifecycle.
Load Occurs when the server control is loaded into the Page
object.
PreRender Occurs after the Control object is loaded but prior to
rendering.
Unload Occurs when the server control is unloaded from memory.
WorkingwithAdRotatorControl
Create a new web page and place an AdRotator control on it.
<div>
<asp:AdRotator ID="AdRotator1"
runat="server" AdvertisementFile ="~/ads.xml"
onadcreated="AdRotator1_AdCreated" />
</div>

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</form>
The ads.xml file and the image files should be located in the root directory of the web
site.
Try to execute the above application and observe that each time the page is reloaded,
the ad is changed.

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The calendar control is a functionally rich web control, which provides the following
capabilities:
 Displaying one month at a time
 Selecting a day, a week or a month
 Selecting a range of days
 Moving from month to month
 Controlling the display of the days programmatically
The basic syntax of a calendar control is:
<asp:Calender ID = "Calendar1" runat = "server"></asp:Calender>
PropertiesandEventsoftheCalendarControl
The calendar control has many properties and events, using which you can customize
the actions and display of the control. The following table provides some important
properties of the Calendar control:
Caption Gets or sets the caption for the calendar control.
CaptionAlign Gets or sets the alignment for the caption.
CellPadding Gets or sets the number of spaces between the data and the
cell border.
CellSpacing Gets or sets the space between cells.
DayHeaderStyle Gets the style properties for the section that displays the
day of the week.
DayNameFormat Gets or sets format of days of the week.
DayStyle Gets the style properties for the days in the displayed
month.
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FirstDayOfWeek Gets or sets the day of week to display in the first column.
NextMonthText Gets or sets the text for next month navigation control. The
default value is >.
NextPrevFormat Gets or sets the format of the next and previous month
navigation control.
OtherMonthDayStyle Gets the style properties for the days on the Calendar
control that are not in the displayed month.
PrevMonthText Gets or sets the text for previous month navigation control.
The default value is <.
SelectedDate Gets or sets the selected date.
SelectedDates Gets a collection of DateTime objects representing the
selected dates.
SelectedDayStyle Gets the style properties for the selected dates.
SelectionMode Gets or sets the selection mode that specifies whether the
user can select a single day, a week or an entire month.
SelectMonthText Gets or sets the text for the month selection element in the
selector column.
SelectorStyle Gets the style properties for the week and month selector
column.
SelectWeekText Gets or sets the text displayed for the week selection
element in the selector column.
ShowDayHeader Gets or sets the value indicating whether the heading for
the days of the week is displayed.
ShowGridLines Gets or sets the value indicating whether the gridlines would
be shown.
ShowNextPrevMonth Gets or sets a value indicating whether next and previous
month navigation elements are shown in the title section.

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ShowTitle Gets or sets a value indicating whether the title section is
displayed.
TitleFormat Gets or sets the format for the title section.
Titlestyle Get the style properties of the title heading for the Calendar
control.
TodayDayStyle Gets the style properties for today's date on the Calendar
control.
TodaysDate Gets or sets the value for today’s date.
UseAccessibleHeader Gets or sets a value that indicates whether to render the
table header <th> HTML element for the day headers
instead of the table data <td> HTML element.
VisibleDate Gets or sets the date that specifies the month to display.
WeekendDayStyle Gets the style properties for the weekend dates on the
Calendar control.
The Calendar control has the following three most important events that allow the
developers to program the calendar control. They are:
Events Description
SelectionChanged It is raised when a day, a week or an entire month is
selected.
DayRender It is raised when each data cell of the calendar control is
rendered.
VisibleMonthChanged It is raised when user changes a month.
WorkingwiththeCalendarControl
Putting a bare-bone calendar control without any code behind file provides a workable
calendar to a site, which shows the months and days of the year. It also allows
navigation to next and previous months.

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Calendar controls allow the users to select a single day, a week, or an entire month.
This is done by using the SelectionMode property. This property has the following
values:
Day To select a single day.
DayWeek To select a single day or an entire week.
DayWeekMonth To select a single day, a week, or an entire month.
None Nothing can be selected.
The syntax for selecting days:
<asp:Calender ID = "Calendar1"
runat = "server"
SelectionMode="DayWeekMonth">
</asp:Calender>
When the selection mode is set to the value DayWeekMonth, an extra column with
the > symbol appears for selecting the week, and a >> symbol appears to the left of
the day’s name for selecting the month.

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Example
The following example demonstrates selecting a date and displays the date in a label:
The content file code is as follows:
Inherits="calendardemo._Default" %>
</head>
<body>
<div>

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<h3> Your Birthday:</h3>
<asp:Calendar ID="Calendar1"
runat="server"
SelectionMode="DayWeekMonth"
onselectionchanged="Calendar1_SelectionChanged">
</asp:Calendar>
</div>
<p>Todays date is:
<asp:Label ID="lblday" runat="server"></asp:Label>
</p>
<p>Your Birday is:
<asp:Label ID="lblbday" runat="server"></asp:Label>
</p>
</form>
</body>
</html>
The event handler for the event SelectionChanged:
protected void Calendar1_SelectionChanged(object sender, EventArgs e)
{
lblday.Text = Calendar1.TodaysDate.ToShortDateString();
lblbday.Text = Calendar1.SelectedDate.ToShortDateString();
}

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When the file is run, it should produce the following output:

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MultiView and View controls allow you to divide the content of a page into different
groups, displaying only one group at a time. Each View control manages one group
of content and all the View controls are held together in a MultiView control.
The MultiView control is responsible for displaying one View control at a time. The
View displayed is called the active view.
The syntax of MultiView control is:
<asp:MultView ID= "MultiView1" runat= "server"></asp:MultiView>
The syntax of View control is:
<asp:View ID= "View1" runat= "server"></asp:View>
However, the View control cannot exist on its own. It would render error if you try to
use it stand-alone. It is always used with a Multiview control as:
<asp:MultView ID= "MultiView1" runat= "server">
<asp:View ID= "View1" runat= "server"> </asp:View>
</asp:MultiView>
PropertiesofView andMultiView Controls
Both View and MultiView controls are derived from Control class and inherit all its
properties, methods, and events. The most important property of the View control is
Visible property of type Boolean, which sets the visibility of a view.
The MultiView control has the following important properties:
Views Collection of View controls within the MultiView.
ActiveViewIndex A zero based index that denotes the active view. If no
view is active, then the index is -1.
The CommandName attribute of the button control associated with the navigation of
the MultiView control are associated with some related field of the MultiView control.
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For example, if a button control with CommandName value as NextView is associated
with the navigation of the multiview, it automatically navigates to the next view when
the button is clicked.
The following table shows the default command names of the above properties:
NextViewCommandName NextView
PreviousViewCommandName PrevView
SwitchViewByIDCommandName SwitchViewByID
SwitchViewByIndexCommandName SwitchViewByIndex
The important methods of the multiview control are:
Methods Description
SetActiveview Sets the active view
GetActiveview Retrieves the active view
Every time a view is changed, the page is posted back to the server and a number of
events are raised. Some important events are:
Events Description
ActiveViewChanged Raised when a view is changed
Activate Raised by the active view
Deactivate Raised by the inactive view
Apart from the above-mentioned properties, methods and events, multiview control
inherits the members of the control and object class.
Example
The example page has three views. Each view has two button for navigating through
the views.

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The content file code is as follows:
Inherits="multiviewdemo._Default" %>
</head>
<body>
<div>
<h2>MultiView and View Controls</h2>
<asp:DropDownList ID="DropDownList1"
runat="server"
onselectedindexchanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>
<hr />
<asp:MultiView ID="MultiView1"
runat="server"
ActiveViewIndex="2"
onactiveviewchanged="MultiView1_ActiveViewChanged" >
<asp:View ID="View1" runat="server">

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<h3>This is view 1</h3>
<br />
<asp:Button CommandName="NextView" ID="btnnext1"
runat="server" Text = "Go To Next" />
<asp:Button CommandArgument="View3"
CommandName="SwitchViewByID" ID="btnlast"
runat="server" Text = "Go To Last" />
</asp:View>
<h3>This is view 2</h3>
<asp:Button CommandName="NextView" ID="btnnext2"
<asp:Button CommandName="PrevView" ID="btnprevious2"
runat="server" Text = "Go To Previous View" />
</asp:View>
<h3> This is view 3</h3>
<br />
<asp:Calendar ID="Calender1" runat="server"></asp:Calendar>
<br />
<asp:Button CommandArgument="0"
CommandName="SwitchViewByIndex" ID="btnfirst"
<asp:Button CommandName="PrevView" ID="btnprevious"

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runat="server" Text = "Go To Previous View" />
</asp:View>
</asp:MultiView>
</div>
</form>
</body>
</html>
The MultiView.ActiveViewIndex determines which view will be shown. This is the only
view rendered on the page. The default value for the ActiveViewIndex is -1, when no
view is shown. Since the ActiveViewIndex is defined as 2 in the example, it shows
the third view, when executed.

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The Panel control works as a container for other controls on the page. It controls the
appearance and visibility of the controls it contains. It also allows generating controls
programmatically.
The basic syntax of panel control is as follows:
<asp:Panel ID= "Panel1" runat = "server"></asp:Panel>
The Panel control is derived from the WebControl class. Hence it inherits all the
properties, methods and events of the same. It does not have any method or event
of its own. However it has the following properties of its own:
BackImageUrl URL of the background image of the panel.
DefaultButton Gets or sets the identifier for the default button that is
contained in the Panel control.
Direction Text direction in the panel.
GroupingText Allows grouping of text as a field.
HorizontalAlign Horizontal alignment of the content in the panel.
ScrollBars Specifies visibility and location of scrollbars within the
panel.
Wrap Allows text wrapping.
WorkingwiththePanelControl
Let us start with a simple scrollable panel of specific height and width and a border
style. The ScrollBars property is set to both the scrollbars, hence both the scrollbars
are rendered.
The source file has the following code for the panel tag:
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<asp:Panel ID="Panel1" runat="server"
BorderColor="#990000"
BorderStyle="Solid"
Borderstyle="width:1px"
Height="116px"
ScrollBars="Both"
style="width:278px">
This is a scrollable panel.
<br />
<br />
<asp:Button ID="btnpanel"
runat="server"
Text="Button"
</asp:Panel>
The panel is rendered as follows:
Example
The following example demonstrates dynamic content generation. The user provides
the number of label controls and textboxes to be generated on the panel. The controls
are generated programmatically.
Change the properties of the panel using the properties window. When you select a
control on the design view, the properties window displays the properties of that
particular control and allows you to make changes without typing.

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The source file for the example is as follows:
<div>
<asp:Panel ID="pnldynamic"
runat="server"
BorderColor="#990000"
BorderStyle="Solid"
Borderstyle="width:1px"
Height="150px"
ScrollBars="Auto"
style="width:60%"
BackColor="#CCCCFF"
Font-Names="Courier"
HorizontalAlign="Center">
This panel shows dynamic control generation:
<br />
<br />
</asp:Panel>

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</div>
<tr>
<td class="style2">No of Labels:</td>
<td class="style1">
<asp:DropDownList ID="ddllabels" runat="server">
<asp:ListItem>0</asp:ListItem>
</asp:DropDownList>
</td>
</tr>
<tr>
</tr>
<tr>
<td class="style2">No of Text Boxes :</td>
<td class="style1">
<asp:DropDownList ID="ddltextbox" runat="server">
<asp:ListItem Value="1"></asp:ListItem>
<asp:ListItem Value="4"></asp:ListItem>

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</asp:DropDownList>
</td>
</tr>
<tr>
</tr>
<tr>
<td class="style2">
<asp:CheckBox ID="chkvisible"
runat="server"
Text="Make the Panel Visible" />
</td>
<td class="style1">
<asp:Button ID="btnrefresh"
runat="server"
Text="Refresh Panel"
</td>
</tr>
</table>
</form>
The code behind the Page_Load event is responsible for generating the controls
dynamically:
{

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{
//make the panel visible
pnldynamic.Visible = chkvisible.Checked;
//generating the lable controls:
int n = Int32.Parse(ddllabels.SelectedItem.Value);
for (int i = 1; i <= n; i++)
{
Label lbl = new Label();
lbl.Text = "Label" + (i).ToString();
pnldynamic.Controls.Add(lbl);
pnldynamic.Controls.Add(new LiteralControl("<br />"));
}
//generating the text box controls:
int m = Int32.Parse(ddltextbox.SelectedItem.Value);
for (int i = 1; i <= m; i++)
{
TextBox txt = new TextBox();
txt.Text = "Text Box" + (i).ToString();
pnldynamic.Controls.Add(txt);
pnldynamic.Controls.Add(new LiteralControl("<br />"));
}
}
}
When executed, the panel is rendered as:

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AJAX stands for Asynchronous JavaScript and XML. This is a cross platform
technology which speeds up response time. The AJAX server controls add script to
the page which is executed and processed by the browser.
However like other ASP.NET server controls, these AJAX server controls also can have
methods and event handlers associated with them, which are processed on the server
side.
The control toolbox in the Visual Studio IDE contains a group of controls called the
'AJAX Extensions'
TheScriptManagerControl
The ScriptManager control is the most important control and must be present on the
page for other controls to work.
It has the basic syntax:
<asp:ScriptManager ID="ScriptManager1" runat="server">
</asp:ScriptManager>
If you create an 'Ajax Enabled site' or add an 'AJAX Web Form' from the 'Add Item'
dialog box, the web form automatically contains the script manager control. The
ScriptManager control takes care of the client-side script for all the server side
controls.
21. AJAX CONTROLS

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143
TheUpdatePanelControl
The UpdatePanel control is a container control and derives from the Control class. It
acts as a container for the child controls within it and does not have its own interface.
When a control inside it triggers a post back, the UpdatePanel intervenes to initiate
the post asynchronously and update just that portion of the page.
For example, if a button control is inside the update panel and it is clicked, only the
controls within the update panel will be affected, the controls on the other parts of
the page will not be affected. This is called the partial post back or the asynchronous
post back.
Example
Add an AJAX web form in your application. It contains the script manager control by
default. Insert an update panel. Place a button control along with a label control
within the update panel control. Place another set of button and label outside the
panel.
The design view looks as follows:
The source file is as follows:
<div>
<asp:ScriptManager ID="ScriptManager1" runat="server" />

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</div>
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Button ID="btnpartial" runat="server"
onclick="btnpartial_Click" Text="Partial PostBack"/>
<br />
<br />
<asp:Label ID="lblpartial" runat="server"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
<p>
</p>
<p>
Outside the Update Panel</p>
<p>
<asp:Button ID="btntotal" runat="server"
onclick="btntotal_Click" Text="Total PostBack" />
</p>
<asp:Label ID="lbltotal" runat="server"></asp:Label>
</form>
Both the button controls have same code for the event handler:
string time = DateTime.Now.ToLongTimeString();
lblpartial.Text = "Showing time from panel" + time;
lbltotal.Text = "Showing time from outside" + time;
Observe that when the page is executed, if the total post back button is clicked, it
updates time in both the labels but if the partial post back button is clicked, it only
updates the label within the update panel.

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A page can contain multiple update panels with each panel containing other controls
like a grid and displaying different part of data.
When a total post back occurs, the update panel content is updated by default. This
default mode could be changed by changing the UpdateMode property of the control.
Let us look at other properties of the update panel.
Properties of the UpdatePanel Control
The following table shows the properties of the update panel control:
ChildrenAsTriggers This property indicates whether the post backs are
coming from the child controls, which cause the update
panel to refresh.
ContentTemplate It is the content template and defines what appears in
the update panel when it is rendered.
ContentTemplateContainer Retrieves the dynamically created template- container
object and used for adding child controls
programmatically.
IsInPartialRendering Indicates whether the panel is being updated as part of
the partial post back.
RenderMode Shows the render modes. The available modes are
Block and Inline.

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UpdateMode Gets or sets the rendering mode by determining some
conditions.
Triggers Defines the collection trigger objects each
corresponding to an event causing the panel to refresh
automatically.
Methods of the UpdatePanel Control
The following table shows the methods of the update panel control:
Methods Description
CreateContentTemplateContainer Creates a Control object that acts as a container
for child controls that define the UpdatePanel
control's content.
CreateControlCollection Returns the collection of all controls that are
contained in the UpdatePanel control.
Initialize Initializes the UpdatePanel control trigger
collection if partial-page rendering is enabled.
Update Causes an update of the content of an
UpdatePanel control.
The behavior of the update panel depends upon the values of the UpdateMode
property and ChildrenAsTriggers property.
UpdateMode ChildrenAsTriggers Effect
Always False Illegal parameters.
Always True UpdatePanel refreshes if whole page
refreshes or a child control on it posts
back.
Conditional False UpdatePanel refreshes if whole page
refreshes or a triggering control outside it
initiates a refresh.

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Conditional True UpdatePanel refreshes if whole page
refreshes or a child control on it posts back
or a triggering control outside it initiates a
refresh.
TheUpdateProgressControl
The UpdateProgress control provides a sort of feedback on the browser while one or
more update panel controls are being updated. For example, while a user logs in or
waits for server response while performing some database oriented job.
It provides a visual acknowledgement like "Loading page...", indicating the work is in
progress.
The syntax for the UpdateProgress control is:
<asp:UpdateProgress ID="UpdateProgress1"
runat="server"
DynamicLayout="true"
AssociatedUpdatePanelID="UpdatePanel1" >
<ProgressTemplate>
Loading...
</ProgressTemplate>
</asp:UpdateProgress>
The above snippet shows a simple message within the ProgressTemplate tag.
However, it could be an image or other relevant controls. The UpdateProgress control
displays for every asynchronous postback unless it is assigned to a single update
panel using the AssociatedUpdatePanelID property.
Properties of the UpdateProgress Control
The following table shows the properties of the update progress control:
AssociatedUpdatePanelID Gets and sets the ID of the update panel with which this
control is associated.
Attributes Gets or sets the cascading style sheet (CSS) attributes of
the UpdateProgress control.

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DisplayAfter Gets and sets the time in milliseconds after which the
progress template is displayed. The default is 500.
DynamicLayout Indicates whether the progress template is dynamically
rendered.
ProgressTemplate Indicates the template displayed during an asynchronous
post back which takes more time than the DisplayAfter
time.
Methods of the UpdateProgress Control
The following table shows the methods of the update progress control:
Methods Description
GetScriptDescriptors Returns a list of components, behaviors, and client controls
that are required for the UpdateProgress control's client
functionality.
GetScriptReferences Returns a list of client script library dependencies for the
UpdateProgress control.
TheTimerControl
The timer control is used to initiate the post back automatically. This could be done
in two ways:
(1) Setting the Triggers property of the UpdatePanel control:
<Triggers>
<asp:AsyncPostBackTrigger
ControlID="btnpanel2"
EventName="Click" />
</Triggers>
(2) Placing a timer control directly inside the UpdatePanel to act as a child control
trigger. A single timer can be the trigger for multiple UpdatePanels.
<asp:UpdatePanel ID="UpdatePanel1"
runat="server"

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UpdateMode="Always">
<ContentTemplate>
<asp:Timer ID="Timer1" runat="server" Interval="1000">
</asp:Timer>
<asp:Label ID="Label1" runat="server"
Height="101px" style="width:304px">
</asp:Label>
</ContentTemplate>
</asp:UpdatePanel>

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A data source control interacts with the data-bound controls and hides the complex
data binding processes. These are the tools that provide data to the data bound
controls and support execution of operations like insertions, deletions, sorting, and
updates.
Each data source control wraps a particular data provider-relational databases, XML
documents, or custom classes and helps in:
 Managing connection
 Selecting data
 Managing presentation aspects like paging, caching, etc.
 Manipulating data
There are many data source controls available in ASP.NET for accessing data from
SQL Server, from ODBC or OLE DB servers, from XML files, and from business objects.
Based on type of data, these controls could be divided into two categories:
 Hierarchical data source controls
 Table-based data source controls
The data source controls used for hierarchical data are:
 XMLDataSource – It allows binding to XML files and strings with or without
schema information.
 SiteMapDataSource – It allows binding to a provider that supplies site map
information.
The data source controls used for tabular data are:
Data source
controls
Description
SqlDataSource It represents a connection to an ADO.NET data provider that
returns SQL data, including data sources accessible via OLEDB
and QDBC.
ObjectDataSource It allows binding to a custom .Net business object that returns
data.
LinqdataSource It allows binding to the results of a Linq-to-SQL query.
(supported by ASP.NET 3.5 only)
AccessDataSource It represents connection to a Microsoft Access database.
22. DATA SOURCES

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DataSourceViews
Data source views are objects of the DataSourceView class, which represent a
customized view of data for different data operations such as sorting, filtering, etc.
The DataSourceView class serves as the base class for all data source view classes,
which define the capabilities of data source controls.
The following table provides the properties of the DataSourceView class:
CanDelete Indicates whether deletion is allowed on the
underlying data source.
CanInsert Indicates whether insertion is allowed on the
CanPage Indicates whether paging is allowed on the
CanRetrieveTotalRowCount Indicates whether total row count information is
available.
CanSort Indicates whether the data could be sorted.
CanUpdate Indicates whether updates are allowed on the
Events Gets a list of event-handler delegates for the data
source view.
Name Name of the view.
The following table provides the methods of the DataSourceView class:
Methods Description
CanExecute Determines whether the specified command
can be executed.

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ExecuteCommand Executes the specific command.
ExecuteDelete Performs a delete operation on the list of data
that the DataSourceView object represents.
ExecuteInsert Performs an insert operation on the list of data
that the DataSourceView object represents.
ExecuteSelect Gets a list of data from the underlying data
storage.
ExecuteUpdate Performs an update operation on the list of
data that the DataSourceView object
represents.
Delete Performs a delete operation on the data
associated with the view.
Insert Performs an insert operation on the data
Select Returns the queried data.
Update Performs an update operation on the data
OnDataSourceViewChanged Raises the DataSourceViewChanged event.
RaiseUnsupportedCapabilitiesError Called by the
RaiseUnsupportedCapabilitiesError method to
compare the capabilities requested for an
ExecuteSelect operation against those that
the view supports.
TheSqlDataSourceControl
The SqlDataSource control represents a connection to a relational database such as
SQL Server or Oracle database, or data accessible through OLEDB or Open Database
Connectivity (ODBC). Connection to data is made through two important properties
ConnectionString and ProviderName.
The following code snippet provides the basic syntax of the control:

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<asp:SqlDataSource runat="server" ID="MySqlSource"
ProviderName='<%$ ConnectionStrings:LocalNWind.ProviderName %>'
ConnectionString='<%$ ConnectionStrings:LocalNWind %>'
SelectionCommand= "SELECT * FROM EMPLOYEES" />
<asp:GridView ID="GridView1" runat="server"
DataSourceID="MySqlSource" />
Configuring various data operations on the underlying data depends upon the various
properties (property groups) of the data source control.
The following table provides the related sets of properties of the SqlDataSource
control, which provides the programming interface of the control:
Property Group Description
DeleteCommand,
DeleteParameters,
DeleteCommandType
Gets or sets the SQL statement, parameters, and type for
deleting rows in the underlying data.
FilterExpression,
FilterParameters
Gets or sets the data filtering string and parameters.
InsertCommand,
InsertParameters,
InsertCommandType
inserting rows in the underlying database.
SelectCommand,
SelectParameters,
SelectCommandType
retrieving rows from the underlying database.
SortParameterName Gets or sets the name of an input parameter that the
command's stored procedure will use to sort data.
UpdateCommand,
UpdateParameters,
updating rows in the underlying data store.

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UpdateCommandType
The following code snippet shows a data source control enabled for data
manipulation:
<asp:SqlDataSource runat="server" ID= "MySqlSource"
ProviderName='<%$ ConnectionStrings:LocalNWind.ProviderName %>'
ConnectionString=' <%$ ConnectionStrings:LocalNWind %>'
SelectCommand= "SELECT * FROM EMPLOYEES"
UpdateCommand= "UPDATE EMPLOYEES SET LASTNAME=@lame"
DeleteCommand= "DELETE FROM EMPLOYEES WHERE EMPLOYEEID=@eid"
FilterExpression= "EMPLOYEEID > 10">
.....
.....
TheObjectDataSourceControl
The ObjectDataSource Control enables user-defined classes to associate the output
of their methods to data bound controls. The programming interface of this class is
almost same as the SqlDataSource control.
Following are two important aspects of binding business objects:
 The bindable class should have a default constructor, it should be stateless,
and have methods that can be mapped to select, update, insert, and delete
semantics.
 The object must update one item at a time, batch operations are not
supported.
Let us go directly to an example to work with this control. The student class is the
class to be used with an object data source. This class has three properties: a student
id, name, and city. It has a default constructor and a GetStudents method for
retrieving data.
The student class:
public class Student
{

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public int StudentID { get; set; }
public string Name { get; set; }
public string City { get; set; }
public Student()
{ }
public DataSet GetStudents()
{
DataSet ds = new DataSet();
DataTable dt = new DataTable("Students");
dt.Columns.Add("StudentID", typeof(System.Int32));
dt.Columns.Add("StudentName", typeof(System.String));
dt.Columns.Add("StudentCity", typeof(System.String));
dt.Rows.Add(new object[] { 1, "M. H. Kabir", "Calcutta" });
dt.Rows.Add(new object[] { 2, "Ayan J. Sarkar", "Calcutta" });
ds.Tables.Add(dt);
return ds;
}
}
Take the following steps to bind the object with an object data source and retrieve
data:
 Create a new web site.
 Add a class (Students.cs) to it by right clicking the project from the Solution
Explorer, adding a class template, and placing the above code in it.
 Build the solution so that the application can use the reference to the class.
 Place an object data source control in the web form.
 Configure the data source by selecting the object.

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 Select a data method(s) for different operations on data. In this example, there
is only one method.
 Place a data bound control such as grid view on the page and select the object
data source as its underlying data source.

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 At this stage, the design view should look like the following:
 Run the project, it retrieves the hard coded tuples from the students class.
TheAccessDataSourceControl
The AccessDataSource control represents a connection to an Access database. It is
based on the SqlDataSource control and provides simpler programming interface.
The following code snippet provides the basic syntax for the data source:
<asp:AccessDataSource ID="AccessDataSource1"
runat="server"
DataFile="~/App_Data/ASPDotNetStepByStep.mdb"
SelectCommand="SELECT * FROM [DotNetReferences]">
</asp:AccessDataSource>
The AccessDataSource control opens the database in read-only mode. However, it
can also be used for performing insert, update, or delete operations. This is done
using the ADO.NET commands and parameter collection.

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Updates are problematic for Access databases from within an ASP.NET application
because an Access database is a plain file and the default account of the ASP.NET
application might not have the permission to write to the database file.

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Every ASP.NET web form control inherits the DataBind method from its parent Control
class, which gives it an inherent capability to bind data to at least one of its
properties. This is known as simple data binding or inline data binding.
Simple data binding involves attaching any collection (item collection) which
implements the IEnumerable interface, or the DataSet and DataTable classes to the
DataSource property of the control.
On the other hand, some controls can bind records, lists, or columns of data into their
structure through a DataSource control. These controls derive from the
BaseDataBoundControl class. This is called declarative data binding.
The data source controls help the data-bound controls implement functionalities such
as sorting, paging, and editing data collections.
The BaseDataBoundControl is an abstract class, which is inherited by two more
abstract classes:
 DataBoundControl
 HierarchicalDataBoundControl
The abstract class DataBoundControl is again inherited by two more abstract classes:
 ListControl
 CompositeDataBoundControl
The controls capable of simple data binding are derived from the ListControl abstract
class and these controls are:
 BulletedList
 CheckBoxList
 DropDownList
 ListBox
 RadioButtonList
The controls capable of declarative data binding (a more complex data binding) are
derived from the abstract class CompositeDataBoundControl. These controls are:
 DetailsView
 FormView
 GridView
 RecordList
23. DATA BINDING

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SimpleDataBinding
Simple data binding involves the read-only selection lists. These controls can bind to
an array list or fields from a database. Selection lists takes two values from the
database or the data source; one value is displayed by the list and the other is
considered as the value corresponding to the display.
Let us take up a small example to understand the concept. Create a web site with a
bulleted list and a SqlDataSource control on it. Configure the data source control to
retrieve two values from your database (we use the same DotNetReferences table as
in the previous chapter).
Choosing a data source for the bulleted list control involves:
 Selecting the data source control
 Selecting a field to display, which is called the data field
 Selecting a field for the value
When the application is executed, check that the entire title column is bound to the
bulleted list and displayed.

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DeclarativeDataBinding
We have already used declarative data binding in the previous tutorial using GridView
control. The other composite data bound controls capable of displaying and
manipulating data in a tabular manner are the DetailsView, FormView, and RecordList
control.
In the next tutorial, we will look into the technology for handling database, i.e,
ADO.NET.
However, the data binding involves the following objects:
 A dataset that stores the data retrieved from the database.
 The data provider, which retrieves data from the database by using a command
over a connection.
 The data adapter that issues the select statement stored in the command
object; it is also capable of update the data in a database by issuing Insert,
Delete, and Update statements.

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Relation between the data binding objects:
Example
Let us take the following steps:
Step (1): Create a new website. Add a class named booklist by right-clicking on the
solution name in the Solution Explorer and choosing the item 'Class' from the 'Add
Item' dialog box. Name it as booklist.cs.
using System;
using System.Data;
using System.Linq;
using System.Web;

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namespace databinding
{
public class booklist
{
protected String bookname;
protected String authorname;
public booklist(String bname, String aname)
{
this.bookname = bname;
this.authorname = aname;
}
public String Book
{
get
{
return this.bookname;
}
set
{
this.bookname = value;
}
}
public String Author
{
get
{

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return this.authorname;
}
set
{
this.authorname = value;
}
}
}
}
Step (2): Add four list controls on the page – a list box control, a radio button list, a
check box list, and a drop down list and four labels along with these list controls. The
page should look like this in design view:
The source file should look as the following:
<div>
<table style="width: 559px">
<tr>
<td style="width: 228px; height: 157px;">
<asp:ListBox ID="ListBox1" runat="server" AutoPostBack="True"

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OnSelectedIndexChanged="ListBox1_SelectedIndexChanged">
</asp:ListBox></td>
<td style="height: 157px">
<asp:DropDownList ID="DropDownList1" runat="server"
AutoPostBack="True"
OnSelectedIndexChanged="DropDownList1_SelectedIndexChanged">
</asp:DropDownList>
</td>
</tr>
<tr>
<td style="width: 228px; height: 40px;">
<asp:Label ID="lbllistbox" runat="server"></asp:Label>
</td>
<asp:Label ID="lbldrpdown" runat="server">
</asp:Label>
</td>
</tr>
<tr>
<td style="width: 228px; height: 21px">
</td>
</td>
</tr>
<tr>
<asp:RadioButtonList ID="RadioButtonList1" runat="server" AutoPostBack="True"
OnSelectedIndexChanged="RadioButtonList1_SelectedIndexChanged">
</asp:RadioButtonList></td>
<asp:CheckBoxList ID="CheckBoxList1" runat="server" AutoPostBack="True"
OnSelectedIndexChanged="CheckBoxList1_SelectedIndexChanged">
</asp:CheckBoxList></td>
</tr>
<tr>

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<asp:Label ID="lblrdlist" runat="server">
</asp:Label></td>
<asp:Label ID="lblchklist" runat="server">
</asp:Label></td>
</tr>
</table>
</div>
</form>
Step (3): Finally, write the following code behind routines of the application:
{
{
IList bklist = createbooklist();
if (!this.IsPostBack)
{
this.ListBox1.DataSource = bklist;
this.ListBox1.DataTextField = "Book";
this.ListBox1.DataValueField = "Author";
this.DropDownList1.DataSource = bklist;
this.DropDownList1.DataTextField = "Book";
this.DropDownList1.DataValueField = "Author";
this.RadioButtonList1.DataSource = bklist;
this.RadioButtonList1.DataTextField = "Book";
this.RadioButtonList1.DataValueField = "Author";
this.CheckBoxList1.DataSource = bklist;
this.CheckBoxList1.DataTextField = "Book";
this.CheckBoxList1.DataValueField = "Author";

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this.DataBind();
}
}
protected IList createbooklist()
{
ArrayList allbooks = new ArrayList();
booklist bl;
bl = new booklist("UNIX CONCEPTS", "SUMITABHA DAS");
allbooks.Add(bl);
bl = new booklist("PROGRAMMING IN C", "RICHI KERNIGHAN");
allbooks.Add(bl);
bl = new booklist("DATA STRUCTURE", "TANENBAUM");
allbooks.Add(bl);
bl = new booklist("NETWORKING CONCEPTS", "FOROUZAN");
allbooks.Add(bl);
bl = new booklist("PROGRAMMING IN C++", "B. STROUSTROUP");
allbooks.Add(bl);
bl = new booklist("ADVANCED JAVA", "SUMITABHA DAS");
allbooks.Add(bl);
return allbooks;
}
protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
{
this.lbllistbox.Text = this.ListBox1.SelectedValue;
}
protected void DropDownList1_SelectedIndexChanged(object sender, EventArgs e)
{
this.lbldrpdown.Text = this.DropDownList1.SelectedValue;

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}
protected void RadioButtonList1_SelectedIndexChanged(object sender, EventArgs e)
{
this.lblrdlist.Text = this.RadioButtonList1.SelectedValue;
}
protected void CheckBoxList1_SelectedIndexChanged(object sender, EventArgs e)
{
this.lblchklist.Text = this.CheckBoxList1.SelectedValue;
}
}
 The booklist class has two properties: bookname and authorname.
 The createbooklist method is a user defined method that creates an array of
booklist objects named allbooks.
 The Page_Load event handler ensures that a list of books is created. The list
is of IList type, which implements the IEnumerable interface and capable of
being bound to the list controls. The page load event handler binds the IList
object 'bklist' with the list controls. The bookname property is to be displayed
and the authorname property is considered as the value.
 When the page is run, if the user selects a book, its name is selected and
displayed by the list controls whereas the corresponding labels display the
author name, which is the corresponding value for the selected index of the
list control.

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ASP.NET allows the users to create controls. These user defined controls are
categorized into:
 User controls
 Custom controls
UserControls
User controls behaves like miniature ASP.NET pages or web forms, which could be
used by many other pages. These are derived from the System.Web.UI.UserControl
class. These controls have the following characteristics:
 They have an .ascx extension.
 They may not contain any <html>, <body>, or <form> tags.
 They have a Control directive instead of a Page directive.
To understand the concept, let us create a simple user control, which will work as
footer for the web pages. To create and use the user control, take the following steps:
1. Create a new web application.
2. Right click on the project folder on the Solution Explorer and choose Add New
Item.
3. Select Web User Control from the Add New Item dialog box and name it
footer.ascx. Initially, the footer.ascx contains only a Control directive.
<%@ Control Language="C#" AutoEventWireup="true"
CodeBehind="footer.ascx.cs"
24. CUSTOM CONTROLS

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Inherits="customcontroldemo.footer" %>
4. Add the following code to the file:
<table>
<tr>
<td align="center"> Copyright ©2010 TutorialPoints Ltd.</td>
</tr>
<tr>
<td align="center"> Location: Hyderabad, A.P </td>
</tr>
</table>
To add the user control to your web page, you must add the Register directive and
an instance of the user control to the page. The following code shows the content
file:
Inherits="customcontroldemo._Default" %>
<%@ Register Src="~/footer.ascx"
TagName="footer" TagPrefix="Tfooter" %>
</head>
<body>
<div>

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<asp:Label ID="Label1" runat="server"
Text="Welcome to ASP.Net Tutorials "></asp:Label>
<br />
<br />
onclick="Button1_Click" Text="Copyright Info" />
</div>
<Tfooter:footer ID="footer1" runat="server" />
</form>
</body>
</html>
When executed, the page shows the footer and this control could be used in all the
pages of your website.
(1) The Register directive specifies a tag name as well as tag prefix for the control.
<%@ Register Src="~/footer.ascx" TagName="footer"
TagPrefix="Tfooter" %>
(2) The following tag name and prefix should be used while adding the user control
on the page:
<Tfooter:footer ID="footer1" runat="server" />

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CustomControls
Custom controls are deployed as individual assemblies. They are compiled into a
Dynamic Link Library (DLL) and used as any other ASP.NET server control. They could
be created in either of the following way:
 By deriving a custom control from an existing control.
 By composing a new custom control combing two or more existing controls.
 By deriving from the base control class.
To understand the concept, let us create a custom control, which will simply render
a text message on the browser. To create this control, take the following steps:
Create a new website. Right click the solution (not the project) at the top of the tree
in the Solution Explorer.
In the New Project dialog box, select ASP.NET Server Control from the project
templates.
The above step adds a new project and creates a complete custom control to the
solution, called ServerControl1. In this example, let us name the project
CustomControls. To use this control, this must be added as a reference to the web
site before registering it on a page. To add a reference to the existing project, right
click on the project (not the solution), and click Add Reference.

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Select the CustomControls project from the Projects tab of the Add Reference dialog
box. The Solution Explorer should show the reference.
To use the control on a page, add the Register directive just below the @Page
directive:
<%@ Register Assembly="CustomControls"
Namespace="CustomControls"
TagPrefix="ccs" %>
Further, you can use the control, similar to any other controls.
<div>
<ccs:ServerControl1 runat="server"
Text = "I am a Custom Server Control" />
</div>
</form>
When executed, the Text property of the control is rendered on the browser as
shown:
WorkingwithCustomControls
In the previous example, the value for the Text property of the custom control was
set. ASP.NET added this property by default, when the control was created. The
following code behind file of the control reveals this.

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using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Text;
using System.Web;
namespace CustomControls
{
[DefaultProperty("Text")]
[ToolboxData("<{0}:ServerControl1
runat=server></{0}:ServerControl1>")]
public class ServerControl1 : WebControl
{
[Bindable(true)]
[Category("Appearance")]
[DefaultValue("")]
[Localizable(true)]
public string Text
{
get
{
String s = (String)ViewState["Text"];
return ((s == null) ? "[" + this.ID + "]" : s);
}
set

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{
ViewState["Text"] = value;
}
}
protected override void RenderContents(HtmlTextWriter output)
{
output.Write(Text);
}
}
}
The above code is automatically generated for a custom control. Events and methods
could be added to the custom control class.
Example
Let us expand the previous custom control named SeverControl1. Let us give it a
method named ‘checkpalindrome’, which gives it a power to check for palindromes.
Palindromes are words/literals that spell the same when reversed. For example,
Malayalam, madam, saras, etc. Extend the code for the custom control, which should
look as:
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Web;
namespace CustomControls
{

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[DefaultProperty("Text")]
[ToolboxData("<{0}:ServerControl1
runat=server></{0}:ServerControl1>")]
public class ServerControl1 : WebControl
{
[Bindable(true)]
[Category("Appearance")]
[DefaultValue("")]
[Localizable(true)]
public string Text
{
get
{
String s = (String)ViewState["Text"];
return ((s == null) ? "[" + this.ID + "]" : s);
}
set
{
ViewState["Text"] = value;
}
}
protected override void RenderContents(HtmlTextWriter output)
{
if (this.checkpanlindrome())
{
output.Write("This is a palindrome: <br />");
output.Write("<FONT size=5 color=Blue>");
output.Write("<B>");

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output.Write(Text);
output.Write("</B>");
output.Write("</FONT>");
}
else
{
output.Write("This is not a palindrome: <br />");
output.Write("<FONT size=5 color=red>");
output.Write("<B>");
output.Write(Text);
output.Write("</B>");
output.Write("</FONT>");
}
}
protected bool checkpanlindrome()
{
if (this.Text != null)
{
String str = this.Text;
String strtoupper = Text.ToUpper();
char[] rev = strtoupper.ToCharArray();
Array.Reverse(rev);
String strrev = new String(rev);
if (strtoupper == strrev)
{
return true;
}
else{

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return false;
}
}
else
{
return false;
}
}
}
}
When you change the code for the control, you must build the solution by clicking
Build -> Build Solution, so that the changes are reflected in your project. Add a text
box and a button control to the page, so that the user can provide a text, it is checked
for palindrome, when the button is clicked.
<div>
Enter a word:
<br />
<asp:TextBox ID="TextBox1" runat="server" style="width:198px">
</asp:TextBox>
<br />
<br />
onclick="Button1_Click"
Text="Check Palindrome" style="width:132px" />
<br />
<br />
<ccs:ServerControl1 ID="ServerControl11"
runat="server" Text = "" />

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</div>
</form>
The Click event handler for the button simply copies the text from the text box to the
text property of the custom control.
{
this.ServerControl11.Text = this.TextBox1.Text;
}
When executed, the control successfully checks palindromes.
(1) When you add a reference to the custom control, it is added to the toolbox and
you can directly use it from the toolbox similar to any other control.
(2) The RenderContents method of the custom control class is overridden here as
you can add your own methods and events.
(3) The RenderContents method takes a parameter of HtmlTextWriter type, which is
responsible for rendering on the browser.

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Websites are designed for repeated visits from the users. Personalization allows a
site to remember the user identity and other information details, and it presents an
individualistic environment to each user.
ASP.NET provides services for personalizing a website to suit a particular client's taste
and preference.
UnderstandingProfiles
ASP.NET personalization service is based on user profile. User profile defines the kind
of information about the user that the site needs. For example, name, age, address,
date of birth, and phone number.
This information is defined in the web.config file of the application and ASP.NET
runtime reads and uses it. This job is done by the personalization providers.
The user profiles obtained from user data is stored in a default database created by
asP.NET. You can create your own database for storing profiles. The profile data
definition is stored in the configuration file web.config.
Example
Let us create a sample site, where we want our application to remember user details
like name, address, date of birth etc. Add the profile details in the web.config file
within the <system.web> element.
<configuration>
<system.web>
<profile>
<properties>
<add name="Name" type ="String"/>
<add name="Birthday" type ="System.DateTime"/>
<group name="Address">
<add name="Street"/>
<add name="City"/>
<add name="State"/>
<add name="Zipcode"/>
25. PERSONALIZATION

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</group>
</properties>
</profile>
</system.web>
</configuration>
When the profile is defined in the web.config file, the profile could be used through
the Profile property found in the current HttpContext and also available via page.
Add the text boxes to take the user input as defined in the profile and add a button
for submitting the data:
Update Page_load to display profile information:
using System;
using System.Data;
using System.Web;

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{
{
if (!this.IsPostBack)
{
ProfileCommon pc=this.Profile.GetProfile(Profile.UserName);
if (pc != null)
{
this.txtname.Text = pc.Name;
this.txtaddr.Text = pc.Address.Street;
this.txtcity.Text = pc.Address.City;
this.txtstate.Text = pc.Address.State;
this.txtzip.Text = pc.Address.Zipcode;
this.Calendar1.SelectedDate = pc.Birthday;
}
}
}
}
Write the following handler for the Submit button, for saving the user data into the
profile:
protected void btnsubmit_Click(object sender, EventArgs e)
{
ProfileCommon pc=this.Profile.GetProfile(Profile.UserName);
if (pc != null)
{

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pc.Name = this.txtname.Text;
pc.Address.Street = this.txtaddr.Text;
pc.Address.City = this.txtcity.Text;
pc.Address.State = this.txtstate.Text;
pc.Address.Zipcode = this.txtzip.Text;
pc.Birthday = this.Calendar1.SelectedDate;
pc.Save();
}
}
When the page is executed for the first time, the user needs to enter the information.
However, next time the user details would be automatically loaded.
Attributesforthe<add>Element
Apart from the name and type attributes that we have used, there are other attributes
to the <add> element. Following table illustrates some of these attributes:
Name The name of the property.
Type By default the type is string but it allows any fully qualified class
name as data type.
serializeAs The format to use when serializing this value.
readOnly A read only profile value cannot be changed, by default this
property is false.
defaultValue A default value that is used if the profile does not exist or does
not have information.
allowAnonymous A Boolean value indicating whether this property can be used
with the anonymous profiles.
Provider The profiles provider that should be used to manage just this
property.

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AnonymousPersonalization
Anonymous personalization allows the user to personalize the site before identifying
themselves. For example, Amazon.com allows the user to add items in the shopping
cart before they log in. To enable this feature, the web.config file could be configured
as:
<anonymousIdentification enabled ="true"
cookieName=".ASPXANONYMOUSUSER"
cookieTimeout="120000"
cookiePath="/"
cookieRequiresSSL="false"
cookieSlidingExpiration="true"
cookieprotection="Encryption"
coolieless="UseDeviceProfile"/>

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Error handling in ASP.NET has three aspects:
 Tracing - tracing the program execution at page level or application level.
 Error handling - handling standard errors or custom errors at page level or
application level.
 Debugging - stepping through the program, setting break points to analyze
the code.
In this chapter, we will discuss tracing and error handling and in the next chapter,
we will discuss debugging.
To understand the concepts, create the following sample application. It has a label
control, a dropdown list, and a link. The dropdown list loads an array list of famous
quotes and the selected quote is shown in the label below. It also has a hyperlink
which points to a nonexistent link.
Inherits="errorhandling._Default" %>
<title>Tracing, debugging and error handling</title>
</head>
<body>
<div>
<asp:Label ID="lblheading" runat="server"
Text="Tracing, Debuggin and Error Handling">
</asp:Label>
<br />
<br />
<asp:DropDownList ID="ddlquotes"
26. ERROR HANDLING

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runat="server" AutoPostBack="True"
onselectedindexchanged="ddlquotes_SelectedIndexChanged">
</asp:DropDownList>
<br />
<br />
<asp:Label ID="lblquotes" runat="server">
</asp:Label>
<br />
<br />
<asp:HyperLink ID="HyperLink1" runat="server"
NavigateUrl="mylink.htm">Link to:</asp:HyperLink>
</div>
</form>
</body>
</html>
The code behind file:
{
{
if (!IsPostBack)
{
string[,] quotes =
{
{"Imagination is more important than Knowledge.", "Albert Einsten"},
{"Assume a virtue, if you have it not", "Shakespeare"},
{"A man cannot be comfortable without his own approval", "Mark
Twain"},
{"Beware the young doctor and the old barber", "Benjamin Franklin"},
{"Whatever begun in anger ends in shame", "Benjamin Franklin"}
};
for (int i=0; i<quotes.GetLength(0); i++)
ddlquotes.Items.Add(new ListItem(quotes[i,0],
quotes[i,1]));
}

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}
protected void ddlquotes_SelectedIndexChanged(object sender, EventArgs e)
{
if (ddlquotes.SelectedIndex != -1)
{
lblquotes.Text = String.Format("{0}, Quote: {1}",
ddlquotes.SelectedItem.Text, ddlquotes.SelectedValue);
}
}
}
Tracing
To enable page-level tracing, you need to modify the Page directive and add a Trace
attribute as shown:
Inherits="errorhandling._Default"
Trace ="true" %>
Now when you execute the file, you get the tracing information:

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It provides the following information at the top:
 Session ID
 Status Code
 Time of Request
 Type of Request
 Request and Response Encoding
The status code sent from the server each time the page is requested shows the
name and time of error if any. The following table shows the common HTTP status
codes:
Number Description
Informational (100 - 199)
100 Continue
101 Switching protocols
Successful (200 - 299)
200 OK
204 No content
Redirection (300 - 399)
301 Moved permanently
305 Use proxy
307 Temporary redirect
Client Errors (400 - 499)
400 Bad request
402 Payment required
404 Not found

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408 Request timeout
417 Expectation failed
Server Errors (500 - 599)
500 Internal server error
503 Service unavailable
505 HTTP version not supported
Under the top level information, there is Trace log, which provides details of page life
cycle. It provides elapsed time in seconds since the page was initialized.
The next section is control tree, which lists all controls on the page in a hierarchical
manner:

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Last in the Session and Application state summaries, cookies, and headers collections
followed by list of all server variables.
The Trace object allows you to add custom information to the trace output. It has
two methods to accomplish this: the Write method and the Warn method.
Change the Page_Load event handler to check the Write method:
{
Trace.Write("Page Load");
if (!IsPostBack)
{
Trace.Write("Not Post Back, Page Load");
string[,] quotes =
.......................
}
}
Run to observe the effects:
To check the Warn method, let us forcibly enter some erroneous code in the selected
index changed event handler:
try
{
int a = 0;
int b = 9 / a;
}
catch (Exception e)

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{
Trace.Warn("UserAction", "processing 9/a", e);
}
Try-Catch is a C# programming construct. The try block holds any code that may or
may not produce error and the catch block catches the error. When the program is
run, it sends the warning in the trace log.
Application level tracing applies to all the pages in the web site. It is implemented by
putting the following code lines in the web.config file:
<system.web>
<trace enabled="true" />
</system.web>
ErrorHandling
Although ASP.NET can detect all runtime errors, still some subtle errors may still be
there. Observing the errors by tracing is meant for the developers, not for the users.
Hence, to intercept such occurrence, you can add error handing settings in the
web.config file of the application. It is application-wide error handling. For example,
you can add the following lines in the web.config file:
<configuration>
<system.web>
<customErrors mode="RemoteOnly"
defaultRedirect="GenericErrorPage.htm">
<error statusCode="403" redirect="NoAccess.htm" />
<error statusCode="404" redirect="FileNotFound.htm" />
</customErrors>
</system.web>
<configuration>
The <customErrors> section has the possible attributes:

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 Mode: It enables or disables custom error pages. It has the three possible
values:
 On: displays the custom pages.
 Off: displays ASP.NET error pages (yellow pages).
 remoteOnly: It displays custom errors to client, display ASP.NET errors locally.
 defaultRedirect: It contains the URL of the page to be displayed in case of
unhandled errors.
To put different custom error pages for different type of errors, the <error> sub tags
are used, where different error pages are specified, based on the status code of the
errors.
To implement page level error handling, the Page directive could be modified:
Inherits="errorhandling._Default"
Trace ="true"
ErrorPage="PageError.htm" %>
Because ASP.NET Debugging is an important subject in itself, so we would discuss it
in the next chapter separately.

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Debugging allows the developers to see how the code works in a step-by-step
manner, how the values of the variables change, how the objects are created and
destroyed, etc.
When the site is executed for the first time, Visual Studio displays a prompt asking
whether it should be enabled for debugging:
When debugging is enabled, the following lines of codes are shown in the web.config:
<system.web>
<compilation debug="true">
<assemblies>
..............
</assemblies>
</compilation>
</system.web>
The Debug toolbar provides all the tools available for debugging:
Breakpoints
Breakpoints specifies the runtime to run a specific line of code and then stop
execution so that the code could be examined and perform various debugging jobs
27. DEBUGGING

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such as changing the value of the variables, step through the codes, moving in and
out of functions and methods etc.
To set a breakpoint, right click on the code and choose insert break point. A red dot
appears on the left margin and the line of code is highlighted as shown:
Next when you execute the code, you can observe its behavior.
At this stage, you can step through the code, observe the execution flow and examine
the value of the variables, properties, objects, etc.
You can modify the properties of the breakpoint from the Properties menu obtained
by right clicking the breakpoint glyph:
The location dialog box shows the location of the file, line number and the character
number of the selected code. The condition menu item allows you to enter a valid
expression, which is evaluated when the program execution reaches the breakpoint:

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The Hit Count menu item displays a dialog box that shows the number of times the
break point has been executed.
Clicking on any option presented by the drop down list opens an edit field where a
target hit count is entered. This is particularly helpful in analyzing loop constructs in
code.

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The Filter menu item allows setting a filter for specifying machines, processes, or
threads or any combination, for which the breakpoint will be effective.
The When Hit menu item allows you to specify what to do when the break point is
hit.
TheDebugWindows
Visual Studio provides the following debug windows, each of which shows some
program information. The following table lists the windows:
Window Description
Immediate Displays variables and expressions.

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Autos Displays all variables in the current and previous
statements.
Locals Displays all variables in the current context.
Watch Displays up to four different sets of variables.
Call Stack Displays all methods in the call stack.
Threads Displays and control threads.

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Most applications are data-centric, however most of the data repositories are
relational databases. Over the years, designers and developers have designed
applications based on object models.
The objects are responsible for connecting to the data access components - called
the Data Access Layer (DAL). Here we have three points to consider:
 All the data needed in an application are not stored in the same source. The
source could be a relation database, some business object, XML file, or a web
service.
 Accessing in-memory object is simpler and less expensive than accessing data
from a database or XML file.
 The data accessed are not used directly, but needs to be sorted, ordered,
grouped, altered etc.
Hence if there is one tool that makes all kind of data access easy that allows joining
data from such disparate data sources and perform standard data processing
operations, in few lines of codes, it would be of great help.
LINQ or Language-Integrated Query is such a tool. LINQ is set of extensions to the
.Net Framework 3.5 and its managed languages that set the query as an object. It
defines a common syntax and a programming model to query different types of data
using a common language.
The relational operators like Select, Project, Join, Group, Partition, Set operations
etc., are implemented in LINQ and the C# and VB compilers in the .Net framework
3.5, which support the LINQ syntax makes it possible to work with a configured data
store without resorting to ASP.NET.
For example, querying the Customers table in the Northwind database, using LINQ
query in C#, the code would be:
var data = from c in dataContext.Customers
where c.Country == "Spain"
select c;
Where:
 The 'from' keyword logically loops through the contents of the collection.
 The expression with the 'where' keyword is evaluated for each object in the
collection.
 The 'select' statement selects the evaluated object to add to the list being
returned.
28. LINQ

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200
 The 'var' keyword is for variable declaration. Since the exact type of the
returned object is not known, it indicates that the information will be inferred
dynamically.
LINQ query can be applied to any data-bearing class that inherits from
IEnumerable<T>, here T is any data type, for example, List<Book>.
Let us look at an example to understand the concept. The example uses the following
class: Books.cs
public class Books
{
public string ID {get; set;}
public string Title { get; set; }
public decimal Price { get; set; }
public DateTime DateOfRelease { get; set; }
public static List<Books> GetBooks()
{
List<Books> list = new List<Books>();
list.Add(new Books { ID = "001",
Title = "Programming in C#",
Price = 634.76m,
DateOfRelease = Convert.ToDateTime("2010-02-05") });
Title = "Learn Jave in 30 days",
Price = 250.76m,
Title = "Programming in ASP.Net 4.0",
Price = 700.00m,

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Title = "VB.Net Made Easy",
Price = 500.99m,
Title = "Programming in C",
Price = 314.76m,
Title = "Programming in C++",
Price = 456.76m,
Title = "Datebase Developement",
Price = 1000.76m,
return list;
}
}
The web page using this class has a simple label control, which displays the titles of
the books. The Page_Load event creates a list of books and returns the titles by using
LINQ query:
public partial class simplequery : System.Web.UI.Page

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{
{
List<Books> books = Books.GetBooks();
var booktitles = from b in books select b.Title;
foreach (var title in booktitles)
lblbooks.Text += String.Format("{0} <br />", title);
}
}
When the page is executed, the label displays the results of the query:
The above LINQ expression:
var booktitles =
from b in books
select b.Title;
Is equivalent to the following SQL query:
SELECT Title from Books
LINQOperators
Apart from the operators used so far, there are several other operators, which
implement all query clauses. Let us look at some of the operators and clauses.

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The Join clause
The 'join clause' in SQL is used for joining two data tables and displays a data set
containing columns from both the tables. LINQ is also capable of that. To check this,
add another class named Saledetails.cs in the previous project:
public class Salesdetails
{
public int sales { get; set; }
public int pages { get; set; }
public string ID {get; set;}
public static IEnumerable<Salesdetails> getsalesdetails()
{
Salesdetails[] sd =
{
new Salesdetails { ID = "001", pages=678, sales = 110000},
};
return sd.OfType<Salesdetails>();
}
}
Add the codes in the Page_Load event handler to query on both the tables using the
join clause:
{

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204
IEnumerable<Books> books = Books.GetBooks();
IEnumerable<Salesdetails> sales = Salesdetails.getsalesdetails();
var booktitles = from b in books
join s in sales
on b.ID equals s.ID
select new { Name = b.Title, Pages = s.pages };
foreach (var title in booktitles)
lblbooks.Text += String.Format("{0} <br />", title);
}
The resulting page is as shown:
The Where clause
The 'where clause' allows adding some conditional filters to the query. For example,
if you want to see the books, where the number of pages are more than 500, change
the Page_Load event handler to:
join s in sales
on b.ID equals s.ID
where s.pages > 500
select new { Name = b.Title, Pages = s.pages };
The query returns only those rows, where the number of pages is more than 500:

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Orderby and Orderbydescending Clauses
These clauses allow sorting the query results. To query the titles, number of pages
and price of the book, sorted by the price, write the following code in the Page_Load
event handler:
join s in sales
on b.ID equals s.ID
orderby b.Price
select new { Name = b.Title,
Pages = s.pages, Price = b.Price};
The returned tuples are:
The Let clause
The let clause allows defining a variable and assigning it a value calculated from the
data values. For example, to calculate the total sale from the above two sales, you
need to calculate:

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TotalSale = Price of the Book * Sales
To achieve this, add the following code snippets in the Page_Load event handler:
The let clause allows defining a variable and assigning it a value calculated from the
data values. For example, to calculate the total sale from the above two sales, you
need to calculate:
join s in sales
on b.ID equals s.ID
let totalprofit = (b.Price * s.sales)
select new { Name = b.Title, TotalSale = totalprofit};
The resulting query page is as shown:

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Implementing security in a site has the following aspects:
 Authentication It is the process of ensuring the user’s identity and
authenticity. ASP.NET allows four types of authentications:
o Windows Authentication
o Forms Authentication
o Passport Authentication
o Custom Authentication
 Authorization: It is the process of defining and allotting specific roles to
specific users.
 Confidentiality: It involves encrypting the channel between the client
browser and the web server.
 Integrity: It involves maintaining the integrity of data. For example,
implementing digital signature.
Forms-BasedAuthentication
Traditionally, forms-based authentication involves editing the web.config file and
adding a login page with appropriate authentication code.
The web.config file could be edited and the following codes written on it:
<system.web>
<authentication mode="Forms">
<forms loginUrl ="login.aspx"/>
</authentication>
<authorization>
<deny users="?"/>
</authorization>
</system.web>
...
...
29. SECURITY

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</configuration>
The login.aspx page mentioned in the above code snippet could have the following
code behind file with the usernames and passwords for authentication hard coded
into it.
protected bool authenticate(String uname, String pass)
{
if(uname == "Tom")
{
if(pass == "tom123")
return true;
}
if(uname == "Dick")
{
if(pass == "dick123")
return true;
}
if(uname == "Harry")
{
if(pass == "har123")
return true;
}
return false;
}
public void OnLogin(Object src, EventArgs e)
{
if (authenticate(txtuser.Text, txtpwd.Text))
{
FormsAuthentication.RedirectFromLoginPage(txtuser.Text, chkrem.Checked);

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}
else
{
Response.Write("Invalid user name or password");
}
}
Observe that the FormsAuthentication class is responsible for the process of
authentication.
However, Visual Studio allows you to implement user creation, authentication, and
authorization with seamless ease without writing any code, through the Web Site
Administration tool. This tool allows creating users and roles.
Apart from this, ASP.NET comes with readymade login controls set, which has
controls performing all the jobs for you.
ImplementingForms-BasedSecurity
To set up forms-based authentication, you need the following:
 A database of users to support the authentication process
 A website that uses the database
 User accounts
 Roles
 Restriction of users and group activities
 A default page to display the login status of the users and other information.
 A login page to allow users to log in, retrieve password, or change password
To create users, take the following steps:
Step (1): Choose Website -> ASP.NET Configuration to open the Web Application
Administration Tool.
Step (2): Click on the Security tab.

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Step (3): Select the authentication type to ‘Forms based authentication’ by selecting
the ‘From the Internet’ radio button.
Step (4): Click on ’Create Users’ link to create some users. If you already had created
roles, you could assign roles to the user, right at this stage.
Step (5): Create a web site and add the following pages:
 Welcome.aspx

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 Login.aspx
 CreateAccount.aspx
 PasswordRecovery.aspx
 ChangePassword.aspx
Step (6): Place a LoginStatus control on the Welcome.aspx from the login section of
the toolbox. It has two templates: LoggedIn and LoggedOut.
In LoggedOut template, there is a login link and in the LoggedIn template, there is a
logout link on the control. You can change the login and logout text properties of the
control from the Properties window.
Step (7): Place a LoginView control from the toolbox below the LoginStatus control.
Here, you can put texts and other controls (hyperlinks, buttons etc.), which are
displayed based on whether the user is logged in or not.
This control has two view templates: Anonymous template and LoggedIn template.
Select each view and write some text for the users to be displayed for each template.
The text should be placed on the area marked red.
Step (8): The users for the application are created by the developer. You might want
to allow a visitor to create a user account. For this, add a link beneath the LoginView
control, which should link to the CreateAccount.aspx page.

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Step (9): Place a CreateUserWizard control on the create account page. Set the
ContinueDestinationPageUrl property of this control to Welcome.aspx.
Step (10): Create the Login page. Place a Login control on the page. The LoginStatus
control automatically links to the Login.aspx. To change this default, make the
following changes in the web.config file.
For example, if you want to name your log in page as signup.aspx, add the following
lines to the <authentication> section of the web.config:
<configuration>
<system.web>
<authentication mode="Forms">
<forms loginUrl ="signup.aspx"
defaultUrl = Welcome.aspx />
</authentication>
</system.web>
</configuration>
Step (11): Users often forget passwords. The PasswordRecovery control helps the
user gain access to the account. Select the Login control. Open its smart tag and click
‘Convert to Template’.
Customize the UI of the control to place a hyperlink control under the login button,
which should link to the PassWordRecovery.aspx.

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Step (12): Place a PasswordRecovery control on the password recovery page. This
control needs an email server to send the passwords to the users.
Step (13): Create a link to the ChangePassword.aspx page in the LoggedIn template
of the LoginView control in Welcome.aspx.

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Step (14): Place a ChangePassword control on the change password page. This
control also has two views.
Now run the application and observe different security operations.
To create roles, go back to the Web Application Administration Tools and click on the
Security tab. Click on ‘Create Roles’ and crate some roles for the application.
Click on the ‘Manage Users’ link and assign roles to the users.

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IISAuthentication:SSL
The Secure Socket Layer or SSL is the protocol used to ensure a secure connection.
With SSL enabled, the browser encrypts all data sent to the server and decrypts all
data coming from the server. At the same time, the server encrypts and decrypts all
data to and from browser.
The URL for a secure connection starts with HTTPS instead of HTTP. A small lock is
displayed by a browser using a secure connection. When a browser makes an initial
attempt to communicate with a server over a secure connection using SSL, the server
authenticates itself by sending its digital certificate.
To use the SSL, you need to buy a digital secure certificate from a trusted Certification
Authority (CA) and install it in the web server. Following are some of the trusted and
reputed certification authorities:
 www.verisign.com
 www.geotrust.com
 www.thawte.com
SSL is built into all major browsers and servers. To enable SSL, you need to install
the digital certificate. The strength of various digital certificates varies depending
upon the length of the key generated during encryption. More the length, more secure
is the certificate, hence the connection.
Strength Description

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40 - bit Supported by most browsers but easy to break
56 - bit Stronger than 40-bit
128 - bit Extremely difficult to break but all the browsers do not
support it.

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WhatisCaching?
Caching is a technique of storing frequently used data/information in memory, so
that, when the same data/information is needed next time, it could be directly
retrieved from the memory instead of being generated by the application.
Caching is extremely important for performance boosting in ASP.NET, as the pages
and controls are dynamically generated here. It is especially important for data
related transactions, as these are expensive in terms of response time.
Caching places frequently used data in quickly accessed media such as the random
access memory of the computer. The ASP.NET runtime includes a key-value map of
CLR objects called cache. This resides with the application and is available via the
HttpContext and System.Web.UI.Page.
In some respect, caching is similar to storing the state objects. However, the storing
information in state objects is deterministic, i.e., you can count on the data being
stored there, and caching of data is nondeterministic.
The data will not be available in the following cases:
 If its lifetime expires,
 If the application releases its memory,
 If caching does not take place for some reason.
You can access items in the cache using an indexer and may control the lifetime of
objects in the cache and set up links between the cached objects and their physical
sources.
CachinginASP.NET
ASP.NET provides the following different types of caching:
 Output Caching: Output cache stores a copy of the finally rendered HTML
pages or part of pages sent to the client. When the next client requests for this
page, instead of regenerating the page, a cached copy of the page is sent, thus
saving time.
 Data Caching: Data caching means caching data from a data source. As long
as the cache is not expired, a request for the data is fulfilled from the cache.
When the cache is expired, fresh data is obtained by the data source and the
cache is refilled.
 Object Caching: Object caching is caching the objects on a page, such as
data-bound controls. The cached data is stored in server memory.
30. DATA CACHING

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 Class Caching: Web pages or web services are compiled into a page class in
the assembly, when run for the first time. Then the assembly is cached in the
server. Next time when a request is made for the page or service, the cached
assembly is referred to. When the source code is changed, the CLR recompiles
the assembly.
 Configuration Caching: Application wide configuration information is stored
in a configuration file. Configuration caching stores the configuration
information in the server memory.
In this tutorial, we consider output caching, data caching, and object caching.
OutputCaching
Rendering a page may involve some complex processes such as, database access,
rendering complex controls etc. Output caching allows bypassing the round trips to
server by caching data in memory. Even the whole page could be cached.
The OutputCache directive is responsible of output caching. It enables output caching
and provides certain control over its behavior.
Syntax for OutputCache directive:
<%@ OutputCache Duration="15" VaryByParam="None" %>
Put this directive under the page directive. This tells the environment to cache the
page for 15 seconds. The following event handler for page load would help in testing
that the page was really cached.
{
Thread.Sleep(10000);
Response.Write("This page was generated and cache at:" +
DateTime.Now.ToString());
}
The Thread.Sleep() method stops the process thread for the specified time. In this
example, the thread is stopped for 10 seconds, so when the page is loaded for first
time, it takes 10 seconds. However, next time you refresh the page it does not take
any time, as the page is retrieved from the cache without being loaded.
The OutputCache directive has the following attributes, which helps in controlling the
behavior of the output cache:
Attribute Values Description

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DiskCacheable true/false Specifies that output could be written to a disk
based cache.
NoStore true/false Specifies that the "no store" cache control
header is sent or not.
CacheProfile String name Name of a cache profile as to be stored in
web.config.
VaryByParam None
*
Param- name
Semicolon delimited list of string specifies query
string values in a GET request or variable in a
POST request.
VaryByHeader *
Header names
Semicolon delimited list of strings specifies
headers that might be submitted by a client.
VaryByCustom Browser
Custom string
Tells ASP.NET to vary the output cache by
browser name and version or by a custom
string.
Location Any
Client
Downstream
Server
None
Any: page may be cached anywhere.
Client: cached content remains at browser.
Downstream: cached content stored in
downstream and server both.
Server: cached content saved only on server.
None: disables caching.
Duration Number Number of seconds the page or control is
cached.
Let us add a text box and a button to the previous example and add this event handler
for the button.
protected void btnmagic_Click(object sender, EventArgs e)
{
Response.Write("<br><br>");

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Response.Write("<h2> Hello, " + this.txtname.Text + "</h2>");
}
Change the OutputCache directive:
<%@ OutputCache Duration="60" VaryByParam="txtname" %>
When the program is executed, ASP.NET caches the page on the basis of the name
in the text box.
DataCaching
The main aspect of data caching is caching the data source controls. We have already
discussed that the data source controls represent data in a data source, like a
database or an XML file. These controls derive from the abstract class
DataSourceControl and have the following inherited properties for implementing
caching:
 CacheDuration - It sets the number of seconds for which the data source will
cache data.
 CacheExpirationPolicy - It defines the cache behavior when the data in cache
has expired.
 CacheKeyDependency - It identifies a key for the controls that auto-expires
the content of its cache when removed.
 EnableCaching - It specifies whether or not to cache the data.
Example
To demonstrate data caching, create a new website and add a new web form on it.
Add a SqlDataSource control with the database connection already used in the data
access tutorials.
For this example, add a label to the page, which would show the response time for
the page.
<asp:Label ID="lbltime" runat="server"></asp:Label>
Apart from the label, the content page is same as in the data access tutorial. Add an
event handler for the page load event:
{
lbltime.Text = String.Format("Page posted at: {0}",
DateTime.Now.ToLongTimeString());

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}
The designed page should look as shown:
When you execute the page for the first time, nothing different happens, the label
shows that, each time you refresh the page, the page is reloaded and the time shown
on the label changes.
Next, set the EnableCaching attribute of the data source control to be 'true' and set
the Cacheduration attribute to '60'. It will implement caching and the cache will expire
every 60 seconds.
The timestamp changes with every refresh, but if you change the data in the table
within these 60 seconds, it is not shown before the cache expires.
<asp:SqlDataSource ID="SqlDataSource1" runat="server"
ConnectionString="<%$ ConnectionStrings:
ASPDotNetStepByStepConnectionString %>"
ProviderName="<%$ ConnectionStrings:
ASPDotNetStepByStepConnectionString.ProviderName %>"
SelectCommand="SELECT * FROM [DotNetReferences]"
EnableCaching="true" CacheDuration = "60">
ObjectCaching
Object caching provides more flexibility than other cache techniques. You can use
object caching to place any object in the cache. The object can be of any type - a

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data type, a web control, a class, a dataset object, etc. The item is added to the
cache simply by assigning a new key name, shown as follows:
Cache["key"] = item;
ASP.NET also provides the Insert() method for inserting an object to the cache. This
method has four overloaded versions. Let us see them:
Overload Description
Cache.Insert((key, value); Inserts an item into the cache with the key name and
value with default priority and expiration.
Cache.Insert(key, value,
dependencies);
Inserts an item into the cache with key, value, default
priority, expiration and a CacheDependency name that
links to other files or items so that when these change
the cache item remains no longer valid.
dependencies,
absoluteExpiration,
slidingExpiration);
This indicates an expiration policy along with the above
issues.
dependencies,
absoluteExpiration,
slidingExpiration, priority,
onRemoveCallback);
This along with the parameters also allows you to set a
priority for the cache item and a delegate that, points
to a method to be invoked when the item is removed.
Sliding expiration is used to remove an item from the cache when it is not used for
the specified time span. The following code snippet stores an item with a sliding
expiration of 10 minutes with no dependencies.
Cache.Insert("my_item", obj, null, DateTime.MaxValue,
TimeSpan.FromMinutes(10));
Example
Create a page with just a button and a label. Write the following code in the page
load event:
{
if (this.IsPostBack)

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{
lblinfo.Text += "Page Posted Back.<br/>";
}
else
{
lblinfo.Text += "page Created.<br/>";
}
if (Cache["testitem"] == null)
{
lblinfo.Text += "Creating test item.<br/>";
DateTime testItem = DateTime.Now;
lblinfo.Text += "Storing test item in cache ";
lblinfo.Text += "for 30 seconds.<br/>";
Cache.Insert("testitem", testItem, null,
DateTime.Now.AddSeconds(30), TimeSpan.Zero);
}
else
{
lblinfo.Text += "Retrieving test item.<br/>";
DateTime testItem = (DateTime)Cache["testitem"];
lblinfo.Text += "Test item is: " + testItem.ToString();
lblinfo.Text += "<br/>";
}
lblinfo.Text += "<br/>";
}
When the page is loaded for the first time, it says:
Page Created.
Creating test item.

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Storing test item in cache for 30 seconds.
If you click on the button again within 30 seconds, the page is posted back but the
label control gets its information from the cache as shown:
Page Posted Back.
Retrieving test item.
Test item is: 14-07-2010 01:25:04

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A web service is a web-based functionality accessed using the protocols of the web
to be used by the web applications. There are three aspects of web service
development:
 Creating the web service
 Creating a proxy
 Consuming the web service
CreatingaWebService
A web service is a web application which is basically a class consisting of methods
that could be used by other applications. It also follows a code-behind architecture
such as the ASP.NET web pages, although it does not have a user interface.
To understand the concept, let us create a web service to provide stock price
information. The clients can query about the name and price of a stock based on the
stock symbol. To keep this example simple, the values are hardcoded in a two-
dimensional array. This web service has three methods:
 A default HelloWorld method
 A GetName Method
 A GetPrice Method
Take the following steps to create the web service:
Step (1): Select File -> New -> Web Site in Visual Studio, and then select ASP.NET
Web Service.
Step (2): A web service file called Service.asmx and its code behind file, Service.cs
is created in the App_Code directory of the project.
Step (3): Change the names of the files to StockService.asmx and StockService.cs.
Step (4): The .asmx file has simply a WebService directive on it:
<%@ WebService Language="C#"
CodeBehind="~/App_Code/StockService.cs"
Class="StockService" %>
Step (5): Open the StockService.cs file, the code generated in it is the basic Hello
World service. The default web service code behind file looks like the following:
using System;
31. WEB SERVICES

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using System.Data;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
namespace StockService
{
/// <summary>
/// Summary description for Service1
/// <summary>
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
[ToolboxItem(false)]
// To allow this Web Service to be called from script,
// using ASP.NET AJAX, uncomment the following line.
// [System.Web.Script.Services.ScriptService]
public class Service1 : System.Web.Services.WebService
{
[WebMethod]
public string HelloWorld()
{
return "Hello World";
}
}
}

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Step (6): Change the code behind file to add the two dimensional array of strings
for stock symbol, name and price and two web methods for getting the stock
information.
using System;
using System.Linq;
using System.Web;
using System.Web.Services;
using System.Web.Services.Protocols;
[WebService(Namespace = "http://tempuri.org/")]
[WebServiceBinding(ConformsTo = WsiProfiles.BasicProfile1_1)]
// To allow this Web Service to be called from script,
// using ASP.NET AJAX, uncomment the following line.
// [System.Web.Script.Services.ScriptService]
public class StockService : System.Web.Services.WebService
{
public StockService () {
//Uncomment the following if using designed components
//InitializeComponent();
}
string[,] stocks =
{
{"RELIND", "Reliance Industries", "1060.15"},
{"ICICI", "ICICI Bank", "911.55"},
{"JSW", "JSW Steel", "1201.25"},
{"WIPRO", "Wipro Limited", "1194.65"},
{"SATYAM", "Satyam Computers", "91.10"}
};

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[WebMethod]
public string HelloWorld() {
return "Hello World";
}
[WebMethod]
public double GetPrice(string symbol)
{
//it takes the symbol as parameter and returns price
for (int i = 0; i < stocks.GetLength(0); i++)
{
if (String.Compare(symbol, stocks[i, 0], true) == 0)
return Convert.ToDouble(stocks[i, 2]);
}
return 0;
}
[WebMethod]
public string GetName(string symbol)
{
// It takes the symbol as parameter and
// returns name of the stock
for (int i = 0; i < stocks.GetLength(0); i++)
{
if (String.Compare(symbol, stocks[i, 0], true) == 0)
return stocks[i, 1];
}
return "Stock Not Found";
}

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}
Step (7): Running the web service application gives a web service test page, which
allows testing the service methods.

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Step (8): Click on a method name, and check whether it runs properly.
Step (9): For testing the GetName method, provide one of the stock symbols, which
are hard coded, it returns the name of the stock
ConsumingtheWebService
For using the web service, create a web site under the same solution. This could be
done by right clicking on the Solution name in the Solution Explorer. The web page
calling the web service should have a label control to display the returned results and
two button controls one for post back and another for calling the service.
The content file for the web application is as follows:
Inherits="wsclient._Default" %>

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</head>
<body>
<div>
<h3>Using the Stock Service</h3>
<br />
<br />
<asp:Label ID="lblmessage" runat="server"></asp:Label>
<br />
<br />
<asp:Button ID="btnpostback" runat="server"
onclick="Button1_Click"
Text="Post Back" style="width:132px" />
<asp:Button ID="btnservice" runat="server"
onclick="btnservice_Click"
Text="Get Stock" style="width:99px" />
</div>
</form>
</body>
</html>

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The code behind file for the web application is as follows:
using System;
using System.Data;
using System.Linq;
using System.Web;
//this is the proxy
using localhost;
namespace wsclient
{
{
{
if (!IsPostBack)
{
lblmessage.Text = "First Loading Time: " +
DateTime.Now.ToLongTimeString();
}

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else
{
lblmessage.Text = "PostBack at: " +
DateTime.Now.ToLongTimeString();
}
}
protected void btnservice_Click(object sender, EventArgs e)
{
StockService proxy = new StockService();
lblmessage.Text = String.Format("Current SATYAM Price:{0}",
proxy.GetPrice("SATYAM").ToString());
}
}
}
CreatingtheProxy
A proxy is a stand-in for the web service codes. Before using the web service, a proxy
must be created. The proxy is registered with the client application. Then the client
application makes the calls to the web service as it were using a local method.
The proxy takes the calls, wraps it in proper format and sends it as a SOAP request
to the server. SOAP stands for Simple Object Access Protocol. This protocol is used
for exchanging web service data.
When the server returns the SOAP package to the client, the proxy decodes
everything and presents it to the client application.
Before calling the web service using the btnservice_Click, a web reference should be
added to the application. This creates a proxy class transparently, which is used by
the btnservice_Click event.
protected void btnservice_Click(object sender, EventArgs e)
{
StockService proxy = new StockService();

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lblmessage.Text = String.Format("Current SATYAM Price: {0}",
proxy.GetPrice("SATYAM").ToString());
}
Take the following steps for creating the proxy:
Step (1): Right click on the web application entry in the Solution Explorer and click
on 'Add Web Reference'.

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Step (2): Select 'Web Services in this solution'. It returns the StockService reference.
Step (3): Clicking on the service opens the test web page. By default the proxy
created is called 'localhost', you can rename it. Click on 'Add Reference' to add the
proxy to the client application.
Include the proxy in the code behind file by adding:
using localhost;

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A thread is defined as the execution path of a program. Each thread defines a unique
flow of control. If your application involves complicated and time consuming
operations such as database access or some intense I/O operations, then it is often
helpful to set different execution paths or threads, with each thread performing a
particular job.
Threads are lightweight processes. One common example of use of thread is
implementation of concurrent programming by modern operating systems. Use of
threads saves wastage of CPU cycle and increases efficiency of an application.
So far we compiled programs where a single thread runs as a single process which is
the running instance of the application. However, this way the application can
perform one job at a time. To make it execute multiple tasks at a time, it could be
divided into smaller threads.
In .Net, the threading is handled through the ‘System.Threading’ namespace.
Creating a variable of the System.Threading.Thread type allows you to create a new
thread to start working with. It allows you to create and access individual threads in
a program.
CreatingThread
A thread is created by creating a Thread object, giving its constructor a ThreadStart
reference.
ThreadStart childthreat = new ThreadStart(childthreadcall);
ThreadLifeCycle
The life cycle of a thread starts when an object of the System.Threading.Thread class
is created and ends when the thread is terminated or completes execution.
Following are the various states in the life cycle of a thread:
 The Unstarted State: It is the situation when the instance of the thread is
created but the Start method is not called.
 The Ready State: It is the situation when the thread is ready to execute and
waiting CPU cycle.
 The Not Runnable State: a thread is not runnable, when:
o Sleep method has been called
o Wait method has been called
o Blocked by I/O operations
32. MULTITHREADING

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 The Dead State: It is the situation when the thread has completed execution
or has been aborted.
ThreadPriority
The Priority property of the Thread class specifies the priority of one thread with
respect to other. The .Net runtime selects the ready thread with the highest priority.
The priorities could be categorized as:
 Above normal
 Below normal
 Highest
 Lowest
 Normal
Once a thread is created, its priority is set using the Priority property of the thread
class.
NewThread.Priority = ThreadPriority.Highest;
Thread:PropertiesandMethods
The Thread class has the following important properties:
CurrentContext Gets the current context in which the thread is executing.
CurrentCulture Gets or sets the culture for the current thread.
CurrentPrinciple Gets or sets the thread's current principal for role-based
security.
CurrentThread Gets the currently running thread.
CurrentUICulture Gets or sets the current culture used by the Resource
Manager to look up culture-specific resources at run time.
ExecutionContext Gets an ExecutionContext object that contains information
about the various contexts of the current thread.

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IsAlive Gets a value indicating the execution status of the current
thread.
IsBackground Gets or sets a value indicating whether or not a thread is a
background thread.
IsThreadPoolThread Gets a value indicating whether or not a thread belongs to
the managed thread pool.
ManagedThreadId Gets a unique identifier for the current managed thread.
Name Gets or sets the name of the thread.
Priority Gets or sets a value indicating the scheduling priority of a
thread.
ThreadState Gets a value containing the states of the current thread.
The Thread class has the following important methods:
Methods Description
Abort Raises a ThreadAbortException in the thread on which it
is invoked, to begin the process of terminating the thread.
Calling this method usually terminates the thread.
AllocateDataSlot Allocates an unnamed data slot on all the threads. For
better performance, use fields that are marked with the
ThreadStaticAttribute attribute instead.
AllocateNamedDataSlot Allocates a named data slot on all threads. For better
performance, use fields that are marked with the
BeginCriticalRegion Notifies a host that execution is about to enter a region of
code in which the effects of a thread abort or unhandled
exception might jeopardize other tasks in the application
domain.

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BeginThreadAffinity Notifies a host that managed code is about to execute
instructions that depend on the identity of the current
physical operating system thread.
EndCriticalRegion Notifies a host that execution is about to enter a region of
code in which the effects of a thread abort or unhandled
exception are limited to the current task.
EndThreadAffinity Notifies a host that managed code has finished executing
instructions that depend on the identity of the current
physical operating system thread.
FreeNamedDataSlot Eliminates the association between a name and a slot, for
all threads in the process. For better performance, use
fields that are marked with the ThreadStaticAttribute
attribute instead.
GetData Retrieves the value from the specified slot on the current
thread, within the current thread's current domain. For
better performance, use fields that are marked with the
GetDomain Returns the current domain in which the current thread is
running.
GetDomainID Returns a unique application domain identifier.
GetNamedDataSlot Looks up a named data slot. For better performance, use
fields that are marked with the ThreadStaticAttribute
attribute instead.
Interrupt Interrupts a thread that is in the WaitSleepJoin thread
state.
Join Blocks the calling thread until a thread terminates, while
continuing to perform standard COM and SendMessage
pumping. This method has different overloaded forms.
MemoryBarrier Synchronizes memory access as follows: The processor
executing the current thread cannot reorder instructions
in such a way that memory accesses prior to the call to
MemoryBarrier execute after memory accesses that follow
the call to MemoryBarrier.

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ResetAbort Cancels an Abort requested for the current thread.
SetData Sets the data in the specified slot on the currently running
thread, for that thread's current domain. For better
performance, use fields marked with the
Start Starts a thread.
Sleep Makes the thread pause for a period of time.
SpinWait Causes a thread to wait the number of times defined by
the iterations parameter.
VolatileRead() Reads the value of a field. The value is the latest written
by any processor in a computer, regardless of the number
of processors or the state of processor cache. This method
has different overloaded forms.
VolatileWrite() Writes a value to a field immediately, so that the value is
visible to all processors in the computer. This method has
Yield Causes the calling thread to yield execution to another
thread that is ready to run on the current processor. The
operating system selects the thread to yield to.
Example
The following example illustrates the uses of the Thread class. The page has a label
control for displaying messages from the child thread. The messages from the main
program are directly displayed using the Response.Write() method. Hence they
appear on the top of the page.
The source file is as follows:
Inherits="threaddemo._Default" %>

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</head>
<body>
<div>
<h3>Thread Example</h3>
</div>
<asp:Label ID="lblmessage" runat="server" Text="Label">
</asp:Label>
</form>
</body>
</html>
The code behind file is as follows:
using System;
using System.Data;
using System.Linq;
using System.Web;

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using System.Threading;
namespace threaddemo
{
{
{
ThreadStart childthreat = new ThreadStart(childthreadcall);
Response.Write("Child Thread Started <br/>");
Thread child = new Thread(childthreat);
child.Start();
Response.Write(
"Main sleeping for 2 seconds.......<br/>");
Thread.Sleep(2000);
Response.Write(
"<br/>Main aborting child thread<br/>");
child.Abort();
}
public void childthreadcall()
{
try{
lblmessage.Text = "<br />Child thread started <br/>";
lblmessage.Text += "Child Thread: Coiunting to 10";

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for( int i =0; i<10; i++)
{
Thread.Sleep(500);
lblmessage.Text += "<br/> in Child thread </br>";
}
lblmessage.Text += "<br/> child thread finished";
}
catch(ThreadAbortException e)
{
lblmessage.Text += "<br /> child thread - exception";
}
finally{
lblmessage.Text += "<br /> child thread
- unable to catch the exception";
}
}
}
}
 When the page is loaded, a new thread is started with the reference of the
method childthreadcall(). The main thread activities are displayed directly on
the web page.
 The second thread runs and sends messages to the label control.
 The main thread sleeps for 2000 ms, during which the child thread executes.
 The child thread runs till it is aborted by the main thread. It raises the
ThreadAbortException and is terminated.
 Control returns to the main thread.
When executed, the program sends the following messages:

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The behavior of an ASP.NET application is affected by different settings in the
configuration files:
 machine.config
 web.config
The machine.config file contains default and the machine-specific value for all
supported settings. The machine settings are controlled by the system administrator
and applications are generally not given access to this file.
An application however, can override the default values by creating web.config files
in its roots folder. The web.config file is a subset of the machine.config file.
If the application contains child directories, it can define a web.config file for each
folder. Scope of each configuration file is determined in a hierarchical top-down
manner.
Any web.config file can locally extend, restrict, or override any settings defined on
the upper level.
Visual Studio generates a default web.config file for each project. An application can
execute without a web.config file, however, you cannot debug an application without
a web.config file.
The following figure shows the Solution Explorer for the sample example used in the
web services tutorial:
33. CONFIGURATION

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In this application, there are two web.config files for two projects i.e., the web service
and the web site calling the web service.
The web.config file has the configuration element as the root node. Information inside
this element is grouped into two main areas: the configuration section-handler
declaration area, and the configuration section settings area.
The following code snippet shows the basic syntax of a configuration file:
<configuration>

<configSections>
<section name="section1" type="section1Handler" />
<section name="section2" type="section2Handler" />
</configSections>

<section1>
<s1Setting1 attribute1="attr1" />
</section1>
<section2>

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<s2Setting1 attribute1="attr1" />
</section2>
<system.web>
<authentication mode="Windows" />
</system.web>
</configuration>
ConfigurationSectionHandlerdeclarations
The configuration section handlers are contained within the <configSections> tags.
Each configuration handler specifies name of a configuration section, contained within
the file, which provides some configuration data. It has the following basic syntax:
<configSections>
<section />
<sectionGroup />
<remove />
<clear/>
</configSections>
It has the following elements:
 Clear - It removes all references to inherited sections and section groups.
 Remove - It removes a reference to an inherited section and section group.
 Section - It defines an association between a configuration section handler
and a configuration element.
 Section group - It defines an association between a configuration section
handler and a configuration section.
ApplicationSettings
The application settings allow storing application-wide name-value pairs for read-only
access. For example, you can define a custom application setting as:
<configuration>
<appSettings>
<add key="Application Name" value="MyApplication" />

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</appSettings>
</configuration>
For example, you can also store the name of a book and its ISBN number:
<configuration>
<appSettings>
<add key="appISBN" value="0-273-68726-3" />
<add key="appBook" value="Corporate Finance" />
</appSettings>
</configuration>
ConnectionStrings
The connection strings show which database connection strings are available to the
website. For example:
<connectionStrings>
<add name="ASPDotNetStepByStepConnectionString"
connectionString="Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=E:projectsdatacaching /
datacachingApp_DataASPDotNetStepByStep.mdb"
providerName="System.Data.OleDb" />
<add name="booksConnectionString"
connectionString="Provider=Microsoft.Jet.OLEDB.4.0;
Data Source=C: databindingApp_Databooks.mdb"
providerName="System.Data.OleDb" />
</connectionStrings>
System.WebElement
The system.web element specifies the root element for the ASP.NET configuration
section and contains configuration elements that configure ASP.NET Web applications
and control how the applications behave.

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It holds most of the configuration elements needed to be adjusted in common
applications. The basic syntax for the element is as given:
<system.web>
<anonymousIdentification>
<authentication>
<authorization>
<browserCaps>
<caching>
<clientTarget>
<compilation>
<customErrors>
<deployment>
<deviceFilters>
<globalization>
<healthMonitoring>
<hostingEnvironment>
<httpCookies>
<httpHandlers>
<httpModules>
<httpRuntime>
<identity>
<machineKey>
<membership>
<mobileControls>
<pages>
<processModel>
<profile>
<roleManager>
<securityPolicy>

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<sessionPageState>
<sessionState>
<siteMap>
<trace>
<trust>
<urlMappings>
<webControls>
<webParts>
<webServices>
<xhtmlConformance>
</system.web>
The following table provides brief description of some of common sub elements of
the system.web element:
AnonymousIdentification
This is required to identify users who are not authenticated when authorization is
required.
Authentication
It configures the authentication support. The basic syntax is as given:
<authentication mode="[Windows|Forms|Passport|None]">
<forms>...</forms>
<passport/>
</authentication>
Authorization
It configures the authorization support. The basic syntax is as given:
<authorization>
<allow .../>
<deny .../>
</authorization>

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Caching
It configures the cache settings. The basic syntax is as given:
<caching>
<cache>...</cache>
<outputCache>...</outputCache>
<outputCacheSettings>...</outputCacheSettings>
<sqlCacheDependency>...</sqlCacheDependency>
</caching>
CustomErrors
It defines custom error messages. The basic syntax is as given:
<customErrors defaultRedirect="url" mode="On|Off|RemoteOnly">
<error. . ./>
</customErrors>
Deployment
It defines configuration settings used for deployment. The basic syntax is as follows:
<deployment retail="true|false" />
HostingEnvironment
It defines configuration settings for hosting environment. The basic syntax is as
follows:
<hostingEnvironment
idleTimeout="HH:MM:SS"
shadowCopyBinAssemblies="true|false"
shutdownTimeout="number"
urlMetadataSlidingExpiration="HH:MM:SS"
/>
Identity
It configures the identity of the application. The basic syntax is as given:

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<identity impersonate="true|false"
userName="domainusername"
password="<secure password>"/>
MachineKey
It configures keys to use for encryption and decryption of Forms authentication cookie
data.
It also allows configuring a validation key that performs message authentication
checks on view-state data and forms authentication tickets. The basic syntax is:
<machineKey
validationKey="AutoGenerate,IsolateApps" [String]
decryptionKey="AutoGenerate,IsolateApps" [String]
validation="HMACSHA256" [SHA1 | MD5 | 3DES | AES | HMACSHA256 |
HMACSHA384 | HMACSHA512 | alg:algorithm_name]
decryption="Auto" [Auto | DES | 3DES | AES | alg:algorithm_name]
/>
Membership
This configures parameters of managing and authenticating user accounts. The basic
syntax is:
<membership
defaultProvider="provider name"
userIsOnlineTimeWindow="number of minutes"
hashAlgorithmType="SHA1">
<providers>...</providers>
</membership>
Pages
It provides page-specific configurations. The basic syntax is:
<pages

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asyncTimeout="number"
autoEventWireup="[True|False]"
buffer="[True|False]"
clientIDMode="[AutoID|Predictable|Static]"
compilationMode="[Always|Auto|Never]"
controlRenderingCompatibilityVersion="[3.5|4.0]"
enableEventValidation="[True|False]"
enableSessionState="[True|False|ReadOnly]"
enableViewState="[True|False]"
enableViewStateMac="[True|False]"
maintainScrollPositionOnPostBack="[True|False]"
masterPageFile="file path"
maxPageStateFieldLength="number"
pageBaseType="typename, assembly"
pageParserFilterType="string"
smartNavigation="[True|False]"
styleSheetTheme="string"
theme="string"
userControlBaseType="typename"
validateRequest="[True|False]"
viewStateEncryptionMode="[Always|Auto|Never]"
>
<controls>...</controls>
<namespaces>...</namespaces>
<tagMapping>...</tagMapping>
<ignoreDeviceFilters>...</ignoreDeviceFilters>
</pages>
Profile

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It configures user profile parameters. The basic syntax is:
<profile
enabled="true|false"
inherits="fully qualified type reference"
automaticSaveEnabled="true|false"
defaultProvider="provider name">
<properties>...</properties>
</profile>
RoleManager
It configures settings for user roles. The basic syntax is:
<roleManager
cacheRolesInCookie="true|false"
cookieName="name"
cookiePath="/"
cookieProtection="All|Encryption|Validation|None"
cookieRequireSSL="true|false "
cookieSlidingExpiration="true|false "
cookieTimeout="number of minutes"
createPersistentCookie="true|false"
defaultProvider="provider name"
domain="cookie domain">
enabled="true|false"
maxCachedResults="maximum number of role names cached"
</roleManager>
SecurityPolicy
It configures the security policy. The basic syntax is:

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<securityPolicy>
<trustLevel />
</securityPolicy>
UrlMappings
It defines mappings to hide the original URL and provide a more user friendly URL.
The basic syntax is:
<urlMappings enabled="true|false">
<add.../>
<clear />
<remove.../>
</urlMappings>
WebControls
It provides the name of shared location for client scripts. The basic syntax is:
<webControls clientScriptsLocation="String" />
WebServices
This configures the web services.

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There are two categories of ASP.NET deployment:
 Local deployment: In this case, the entire application is contained within a
virtual directory and all the contents and assemblies are contained within it
and available to the application.
 Global deployment: In this case, assemblies are available to every
application running on the server.
There are different techniques used for deployment, however, we will discuss the
following most common and easiest ways of deployment:
 XCOPY deployment
 Copying a Website
 Creating a set up project
XCOPYDeployment
XCOPY deployment means making recursive copies of all the files to the target folder
on the target machine. You can use any of the commonly used techniques:
 FTP transfer
 Using Server management tools that provide replication on a remote site
 MSI installer application
XCOPY deployment simply copies the application file to the production server and
sets a virtual directory there. You need to set a virtual directory using the Internet
Information Manager Microsoft Management Console (MMC snap-in).
CopyingaWebsite
The Copy Web Site option is available in Visual Studio. It is available from the Website
-> Copy Web Site menu option. This menu item allows copying the current web site
to another local or remote location. It is a sort of integrated FTP tool.
Using this option, you connect to the target destination, select the desired copy
mode:
 Overwrite
 Source to Target Files
 Sync UP Source And Target Projects
Then proceed with copying the files physically. Unlike the XCOPY deployment, this
process of deployment is done from Visual Studio environment. However, there are
following problems with both the above deployment methods:
34. DEPLOYMENT

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 You pass on your source code.
 There is no pre-compilation and related error checking for the files.
 The initial page load will be slow.
CreatingaSetupProject
In this method, you use Windows Installer and package your web applications so it
is ready to deploy on the production server. Visual Studio allows you to build
deployment packages. Let us test this on one of our existing project, say the data
binding project.
Open the project and take the following steps:
Step (1): Select File -> Add -> New Project with the website root directory
highlighted in the Solution Explorer.
Step (2): Select Setup and Deployment, under Other Project Types. Select Setup
Wizard.

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Step (3): Choosing the default location ensures that the set up project will be located
in its own folder under the root directory of the site. Click on okay to get the first
splash screen of the wizard.
Step (4): Choose a project type. Select 'Create a setup for a web application'.

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Step (5): Next, the third screen asks to choose project outputs from all the projects
in the solution. Check the check box next to 'Content Files from...'
Step (6): The fourth screen allows including other files like ReadMe. However, in our
case there is no such file. Click on finish.

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Step (7): The final screen displays a summary of settings for the set up project.
Step (8): The Set up project is added to the Solution Explorer and the main design
window shows a file system editor.

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Step (9): Next step is to build the setup project. Right-click on the project name in
the Solution Explorer and select Build.
Step (10): When build is completed, you get the following message in the Output
window:
Two files are created by the build process:
 Setup.exe
 Setup-databinding.msi
You need to copy these files to the server. Double-click the setup file to install the
content of the .msi file on the local machine.

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