/* Add a class to a string */
String.prototype.addClass = function(theClass) {
	if (this != "") {
		if (!this.classExists(theClass)) {
			return this+" "+theClass;
		}
	} else {
		return theClass;
	}
	return this;
};

/* Check if a class exists in a string */
String.prototype.classExists = function(theClass) {
	var regString = "(^| )"+theClass+"\W*";
	var regExpression = new RegExp(regString);
	if (regExpression.test(this)) {
		return true;
	}
	return false;
};

/* Remove a class from a string */
String.prototype.removeClass = function(theClass) {
	var regString = "(^| )"+theClass+"\W*";
	var regExpression = new RegExp(regString);
	return this.replace(regExpression, "");
};

String.prototype.validEmail = function() {
	if (this.match(/^[\w\.\-]+@([\w\-]+\.)+[a-zA-Z]+$/))
	return true;
	return false;
};