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 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()) + ';path=/';
 }

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