function SetCookie(name,value,expire) {   
    var exp  = new Date();   
    exp.setTime(exp.getTime() + expire);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString()+';path=/';   
}   
  
function getCookie(name) {   
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));   
    if(arr != null) return unescape(arr[2]); return null;   
}   
  
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();
}