JavaScript raw has/add/remove Class

js.class.js

Element.prototype.hasClassName = function(className) {
	return this.classList ? this.classList.contains(className) : !!this.className.match(new RegExp('(\\s|^)' + className + '(\\s|$)'));
}
Element.prototype.addClass = function(className) {
	if (this.classList){this.classList.add(className);}
	else if (!this.hasClass(className)){this.className += " " + className;}
	return this;
}
Element.prototype.removeClass = function(className) {
	if (this.classList){this.classList.remove(className);}
	else if (this.hasClass(className)) {
		var reg = new RegExp('(\\s|^)' + className + '(\\s|$)');
		this.className = this.className.replace(reg, ' ');
	}
	return this;
}