String.prototype.contains = function (string, s) {
	return (s) ? ((s + this + s).indexOf(s + string + s) > -1) : (this.indexOf(string) > -1);
};
String.prototype.trim = function () {
	return this.replace(/^\s+|\s+$/g, '');
};
if (!(Array.prototype.indexOf && Array.prototype.contains)) {
	Array.prototype.indexOf = function (item, from) {
		var len = this.length;
		for (var i = (from < 0) ? Math.max(0, len + from) : from || 0; i < len; i++){
			if (this[i] === item) return i;
		}
		return -1;
	};
	Array.prototype.contains = function (item, from) {
		return (this.indexOf(item, from) != -1);
	};
}
function hasClass(element, className) {
	if (!element.className)	return false;
	return element.className.contains(className, ' ');
}
function addClassToElement(element, className) {
//	if (typeof(element.className) != 'string')	return;
	if (hasClass(element, className))	return;
	element.className = (element.className + ' ' + className).trim();
}
function removeClassFromElement(element, className) {
	if (!element.className)	return;
	if (!hasClass(element, className))	return;
	element.className = element.className.replace(className, '').replace(/\s+/g, ' ').trim();
}
function toggleClass(element, className) {
	if (hasClass(element, className)) {
		removeClassFromElement(element, className);
	} else {
		addClassToElement(element, className);
	}
}
if (!document.getElementsByClassName) {
	document.getElementsByClassName = function (className) {
		var result = [];
		if (document.evaluate) {
			var xpath = document.evaluate(
				'.//*[contains(concat(" ", @class, " "), " ' + className + ' ")]',
				document,
				(function(prefix){return(prefix=='xhtml')?'http://www.w3.org/1999/xhtml':false;}),
				7,	// XPathResult.ORDERED_NODE_SNAPSHOT_TYPE
				null
			);
			for (var i = 0, j = xpath.snapshotLength; i < j; i++) result.push(xpath.snapshotItem(i));
		} else {
			var elements = ((document.all) ? document.all : document.getElementsByTagName('*'));
			for (var i = 0; i < elements.length; i++) {
				var el = elements[i] || elements.item(i);
				if (hasClass(el, className)) {
					result[result.length] = el;
				}
			}
		}
		return result;
	};
}
function addEventToElement(element, evtName, fn) {
	if (element.addEventListener) {
		element.addEventListener(evtName, fn, false);
	} else if (element.attachEvent) {
		element.attachEvent('on' + evtName, (function (bind) {
			return function (evt) {
				fn.call(bind, evt);
			};
		})(element));
	} else {
		var fn_org = element['on' + evtName];
		element['on' + evtName] = function (event) {
			fn.call(element, event);
			if (fn_org)	fn_org.call(element, event);
		}
	}
}