Javascript Array forEach() Method

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Description:

Javascript array forEach() method calls a function for each element in the array.

Syntax:

array.forEach(callback[, thisObject]);

Here is the detail of parameters:

callback : Function to test each element of the array.
thisObject : Object to use as this when executing callback.

Return Value:

Returns created array.

Compatibility:

This method is a JavaScript extension to the ECMA-262 standard; as such it may not be present in other implementations of the standard. To make it work you need to add following code at the top of your script:

if (!Array.prototype.forEach){  Array.prototype.forEach = function(fun /*, thisp*/)  {    var len = this.length;    if (typeof fun != "function")      throw new TypeError();    var thisp = arguments[1];    for (var i = 0; i < len; i++)    {      if (i in this)        fun.call(thisp, this[i], i, this);    }  };}

Example:

<html><head><title>JavaScript Array forEach Method</title></head><body><script type="text/javascript">if (!Array.prototype.forEach){  Array.prototype.forEach = function(fun /*, thisp*/)  {    var len = this.length;    if (typeof fun != "function")      throw new TypeError();    var thisp = arguments[1];    for (var i = 0; i < len; i++)    {      if (i in this)        fun.call(thisp, this[i], i, this);    }  };}function printBr(element, index, array) {  document.write("<br />[" + index + "] is " + element ); }[12, 5, 8, 130, 44].forEach(printBr);  </script></body></html>

This will produce the follow result:

[0] is 12[1] is 5[2] is 8[3] is 130[4] is 44

reference:

http://www.tutorialspoint.com/javascript/array_foreach.htm

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