CSSClass.js

// add indexOf to Array prototype for IE<8
// this isn't failsafe, but it works on our behalf
Array.prototype.CSSClassIndexOf = Array.prototype.indexOf || function (item) {
	var length = this.length;
	for (var i = 0; i<length; i++)
		if (this[i]===item) return i;
	return -1;
};
// actual Element prototype manipulation
var p = Element.prototype;
if(!p.hasClass)
	p.hasClass = function(c) {
		var r = true, e = this.className.split(' '); c = c.split(' ');
		for(var i=0; i<c.length; i++)
			if(e.CSSClassIndexOf(c[i])===-1)
				r = false;
		return r;
	};
if(!p.addClass)
	p.addClass = function(c) {
		c = c.split(' ');
		for(var i=0; i<c.length; i++)
			if(!this.hasClass(c[i]))
				this.className = this.className!==''?(this.className+' '+c[i]):c[i];
		return this;
	};
if(!p.removeClass)
	p.removeClass = function(c) {
		var e = this.className.split(' '); c = c.split(' ');
		for(var i=0; i<c.length; i++)
			if(this.hasClass(c[i]))
				e.splice(e.CSSClassIndexOf(c[i]), 1);
		this.className = e.join(' ');
		return this;
	};
if(!p.toggleClass)
	p.toggleClass = function(c) {
		c = c.split(' ');
		for(var i=0; i<c.length; i++)
			if (this.hasClass(c[i]))
				this.removeClass(c[i]);
			else
				this.addClass(c[i]);
		return this;
	};