Javascript function

 Specifies the number of arguments
expected by the function.
 Syntax
› functionName.length

 console.log( (function () {}).length );
 console.log( (function (a) {}).length );
 console.log( (function (a, b) {}).length );

 function ArgTest(a, b){
 var s = "";
 s += "Expected Arguments: " + ArgTest.length;
 s += "<br />";
 s += "Passed Arguments: " + arguments.length;
 return s;
 }

 Calls a function with a given this value and
arguments provided individually.
 Syntax
› fun.call(thisArg[, arg1[, arg2[, ...]]])

 function diplayInfo(year, month, day){
 return "Name:" + this.name + ";birthday:" + year +
"." + month + "." + day;
 }
 var p = { name: "Jason" };
 diplayInfo.call(p, 1985, 11, 5);

 Calls a function with a given this value
and arguments provided as an array
 Syntax
› fun.apply(thisArg[, argsArray])

 function diplayInfo(year, month, day){
 return "Name:" + this.name + ";birthday:" + year +
 "." + month + "." + day;
 }
 var p = { name: "Jason" };
 console.log(diplayInfo.apply(p, [1985, 11, 5]));

 Specifies the currently executing function
 callee is a property of the arguments object.
 Syntax
› [function.]arguments.callee

 function factorial(n){
 if (n <= 0)
 return 1;
 else
 return n * arguments.callee(n - 1);
 }
 factorial(4);

 Creates a new function that, when
called, has its this keyword set to the
provided value, with a given sequence
of arguments preceding any provided
when the new function is called.
 Syntax
fun.bind(thisArg[, arg1[, arg2[, ...]]])

 var x = 9;
 var module = {
 x: 81,
 getX: function() { return this.x; }
 };
 module.getX(); //Answer: ?
 var getX = module.getX;
 getX(); //Answer: ?
 var boundGetX = getX.bind(module);
 boundGetX(); //Answer: ?
 module.x = 100;
 boundGetX(); //Answer: ?

 var checkNumericRange = function (value) {
 return value >= this.min && value <= this.max;
 }
 var range = { min: 10, max: 20 };
 var boundCheckNumericRange =
checkNumericRange.bind(range);
 var result = boundCheckNumericRange (12);
 Result = ??

 var displayArgs = function (val1, val2, val3, val4) {
 console.log(val1 + " " + val2 + " " + val3 + " " +
val4);
 }
 var emptyObject = {};
 var displayArgs2 =
displayArgs.bind(emptyObject, 12, "a");
 displayArgs2("b", "c"); //Answer: ?

 Javascript MDN
› https://developer.mozilla.org/en-
US/docs/Web/JavaScript/Reference/Global_Obj
ects/Function
 Javascript MSDN
› http://teamserver:8080/tfs/DefaultCollection/!Ba
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Javascript function

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Javascript function