function setCookie(NameOfCookie, value, expiredays) {
	var ExpireDate = new Date ();
	ExpireDate.setTime(ExpireDate.getTime() + (expiredays * 24 * 3600 * 1000));
	document.cookie = NameOfCookie + "=" + escape(value) + ((expiredays == null) ? "" : "; expires=" + ExpireDate.toGMTString());
}

function getCookie(NameOfCookie) {
  if (document.cookie.length > 0)
  { begin = document.cookie.indexOf(NameOfCookie+"=");
   if (begin != -1)
   { begin += NameOfCookie.length+1;
     end = document.cookie.indexOf(";", begin);
   if (end == -1) end = document.cookie.length;
  return unescape(document.cookie.substring(begin, end)); }
  }
return null;
}

function delCookie (NameOfCookie)
{
	if (getCookie(NameOfCookie)) {
		document.cookie = NameOfCookie + "=" + "; expires=Thu, 01-Jan-70 00:00:01 GMT";
	}
}