Using advanced C# features in Sharepoint development
- 1. Alexey Sadomov, PhD, Sharepoint MVP http://sadomovalex.blogspot.com/
- 2. Efficient way to troubleshoot issues, which are not reproduced on dev environment Page is opened in context of living site, e.g. http://example.com/_layouts/test.aspx Do not require updates of wsp packages Do not require installations of dlls into the GAC Can be easily removed from production after troubleshooting without leaving security holes C# 2.0 is available by default for server scripts
- 3. Example: trace info about thread principal and currently logged Sharepoint user
- 4. Example: trace info about thread principal and currently logged Sharepoint user
- 5. Enable features of C# 3.0 in _layouts pages via web.config: All features of C# 3.0 become available (e.g. lambdas, query expressions, etc.): see Overview of C# 3.0
- 6. Sharepoint 2013 preview: Web sites are created with .Net 4.0 app pools Default compiler is set to version 4.0 It is possible to use features of C# 4 (e.g. dynamic types) in embedded server scripts without additional configurations
- 7. Use when can’t solve problem with standard tools Requires preliminary investigation of Sharepoint code: JetBrains dotPeek Telerik JustCompile Reflector Where to search Sharepoint dlls: GAC 14/ISAPI inetpub...mywebapp_app_bin
- 8. Real life example: Create instance of SPSite in SPSecurity.RunWithElevatedPrivileges() method Open SPWeb Code is executed under SHAREPOINTSystem account (app pool identity) Call standard API which in turns uses SPContext.Current.Site or SPContext.Current.Web Result: access denied page
- 9. Analyzing code of SPContext:
- 10. Analyzing code of SPContext:
- 11. Use knowledge of Sharepoint code and reflection for solving the problem:
- 12. ReflectionHelper code:
- 13. Can be used for generating and executing a method at run time, without having to generate a dynamic assembly and a dynamic type to contain the method The executable code created by the just-in-time (JIT) compiler is reclaimed when the DynamicMethod object is reclaimed If the dynamic method is associated with specific type, it has access to all members of the type, regardless of access level Dynamic methods and their parameters do not have to be named Allows to avoid some limitations of C#: e.g. although dynamic methods are static methods the relaxed rules for delegate binding allow a dynamic method to be bound to an object, so that it acts like an instance method when called using that delegate instance
- 14. Example: dynamic method for calculating factorial
- 15. How it can be used in Sharepoint? Example: use Telerik RadEditor in all sub sites in web application without feature activations RadEditorFeature – overrides rendering template for RichTextField with Telerik control RadEditorFeatureIE – “flag” feature, depends on RadEditorFeature Technically it is enough to activate RadEditorFeature once For new sites: Activate features manually Use feature stappling for OTB site definitions Modify onet.xml file for custom site definitions
- 16. Where problem is coming from? RadHtmlListField class:
- 17. Solution: Define new class inheritor of RadHtmlListField Define OnLoad() by the same way as in RadHtmlListField using reflection Always return true from ShowEditorOnPage() method Inheritance chain: AllBrowsersHtmlListField –> RadHtmlListField –> MOSSRadEditor The problem: how to call MOSSRadEditor.OnLoad() from AllBrowsersHtmlListField.OnLoad() without caling RadHtmlListField .OnLoad()? I.e. we need to skip one tier in the inheritance chain and call virtual method OnLoad(), but not from base class, but from base of base class Answer: no how in standard C# Can dynamic method help here? Yes
- 18. Example: create dynamic method for skipping one tier in virtual members calls
- 19. Camlex – open source project which simplifies creating of CAML queries for SharePoint by using expression trees Uses expression trees and lambda expressions for generating CAML Simplifies creation of dynamic CAML queries when conditions are calculated in runtime Doesn’t require knowledge of CAML from developers Supports native .Net types and Sharepoint-specific types http://camlex.codeplex.com/
- 20. Example of usage: Direct translator:
- 21. Camlex 3.0 Reverse Engineering – creates expression trees based on strings Reverse Engineering translator:
- 22. Camlex Re + ExpressionToCode = Camlex Online: http://camlex-online.org/ Simplifies usage of Camlex for developers who didn’t have experience with it yet Quick refactoring of existing hard-coded CAML queries to Camlex Fully reversible CAML query schema opens many interesting applications in future Example of combining of several non-trivial OSS projects
- 23. Add conditions to existing string queries using lambda expressions:
- 24. Expand ViewFields, GroupBy, OrderBy:
- 25. Built-in to OS, doesn’t need VS for writing and running C# programs May be useful: if you already have a code which want to reuse have existing C# code which is hard to move to PowerShell for developers who know C#, but only started work with PowerShell if you want to run quick test, but don’t want to run VS and compile dll C# 3.0 can be used: -Language CSharpVersion3 Can specify existing assemblies or source code files
- 26. Example: enumerate sub-sites using C# code in PowerShell
- 27. http://sadomovalex.blogspot.com/ Use C# 3.0 features in application layout pages in Sharepoint: http://sadomovalex.blogspot.fi/2010/12/use-c-30-features-in- application-layout.html Use Telerik Rad Editor Lite without features activation: http://sadomovalex.blogspot.fi/2011/12/use-telerik-rad-editor-lite- without.html Generating Dynamic Methods with Expression Trees in Visual Studio 2010: http://blogs.msdn.com/b/csharpfaq/archive/2009/09/14/generating- dynamic-methods-with-expression-trees-in-visual-studio-2010.aspx Camlex project site: http://camlex.codeplex.com/ Camlex online: http://camlex-online.org/ ExpressionToCode: http://code.google.com/p/expressiontocode/ Materials from followings sites are used for presentation: http://newswallpapers1.blogspot.com, http://arts-wallpapers.com, http://www.fanpop.com, http://wallpaperswide.com, http://starwars.wikia.com