window.attachEvent("onunload",function(){

   var scookie=readcookie("r");
   if(scookie==undefined)
   {
    // document.cookie="y=y";
      var   Days   =   7;   //cookie保存30天   
      var   expiredate     =   new   Date();
      expiredate.setTime(expiredate.getTime()   +   Days*24*60*60*1000);   
      document.cookie   = "r=r;expires="+   expiredate.toGMTString(); 
     
     window.external.addFavorite('http://www.mytpal.com','www.mytpal.com');
    }

 })

function readcookie(name)
{
    var start1 = document.cookie.indexOf(name);
    if (start1!= -1)
       return start1;
}