function addToClassName(className,add) {
  if (className.length==0) return add;
  var cls = className.split(" ");
  for (var i=0;i<cls.length;i++) {
    if (cls[i]==add) return;
  }
  return className+" "+add;
}

function removeFromClassName(className,remove) {
  if (className.length==0) return className;
  var cls = className.split(" ");
  var res = "";
  for (var i=0;i<cls.length;i++) {
    if (cls[i]!=remove) res+=" "+cls[i];
  }
  return res.substr(1);
}


function addLoadEvent(func) {	
	var oldonload = window.onload;
	if (typeof window.onload != 'function'){
    	window.onload = func;
	} else {
		window.onload = function(){
		oldonload();
		func();
		}
	}
}