Dean Edwards forEach function.

Dean Edwards

Javascript Code

/*
	forEach, version 1.0
	Copyright 2006, Dean Edwards
	License: http://www.opensource.org/licenses/mit-license.php
*/

// array-like enumeration
if (!Array.forEach) { // mozilla already supports this
	Array.forEach = function(array, block, context) {
		for (var i = 0; i < array.length; i++) {
			block.call(context, array[i], i, array);
		}
	};
}

// generic enumeration
Function.prototype.forEach = function(object, block, context) {
	for (var key in object) {
		if (typeof this.prototype[key] == "undefined") {
			block.call(context, object[key], key, object);
		}
	}
};

// character enumeration
String.forEach = function(string, block, context) {
	Array.forEach(string.split(""), function(chr, index) {
		block.call(context, chr, index, string);
	});
};

// globally resolve forEach enumeration
var forEach = function(object, block, context) {
	if (object) {
		var resolve = Object; // default
		if (object instanceof Function) {
			// functions have a "length" property
			resolve = Function;
		} else if (object.forEach instanceof Function) {
			// the object implements a custom forEach method so use that
			object.forEach(block, context);
			return;
		} else if (typeof object == "string") {
			// the object is a string
			resolve = String;
		} else if (typeof object.length == "number") {
			// the object is array-like
			resolve = Array;
		}
		resolve.forEach(object, block, context);
	}
};

Usage:

forEach(ary,function(element){
	// do something with (or use) element
});