js cookie

function setCookie(name, value) {
   var exp = new Date();
   exp.setTime(exp.getTime() + 24 * 60 * 60 * 1000);
   document.cookie = name + "=" + escape(value) + ";expires=" + exp.toGMTString();
}
function getCookie(name)
{
   var regExp = new RegExp("(^| )" + name + "=([^;]*)(;|$)");
   var arr = document.cookie.match(regExp);
   if (arr == null) {
      return null;
   }
   return unescape(arr[2]);
}
function delCookie(name)
   {
      var exp = new Date();
      exp.setTime(exp.getTime() - 1);
      var cval=getCookie(name);
      if(cval!=null)
         document.cookie= name + "="+cval+";expires="+exp.toGMTString();
   }