JavaScript hasClass, addClass, removeClass

gistfile1.js

// JavaScript hasClass, addClass, removeClass
//source: http://www.avoid.org/?p=78

function hasClass(el, name) {
   return new RegExp('(\\s|^)'+name+'(\\s|$)').test(el.className);
}

function addClass(el, name)
{
   if (!hasClass(el, name)) { el.className += (el.className ? ' ' : '') +name; }
}

function removeClass(el, name)
{
   if (hasClass(el, name)) {
      el.className=el.className.replace(new RegExp('(\\s|^)'+name+'(\\s|$)'),' ').replace(/^\s+|\s+$/g, '');
   }
}