Javascript: Add/Remove classes from elements

Here's a simple way of achiving this without any bloating libraries (I.e. JQuery etc.)
There is also a 'HasClass' method, which becomes quite useful.

function hasClass(ele, cls) {

    return ele.className.match(new RegExp('(\\s|^)' + cls + '(\\s|$)'));

}

function addClass(ele, cls) {

    if (!this.hasClass(ele, cls)) ele.className += " " + cls;

}

function removeClass(ele, cls) {

    if (hasClass(ele, cls)) {

        var reg = new RegExp('(\\s|^)' + cls + '(\\s|$)');

        ele.className = ele.className.replace(reg, ' ');

    }

}