function stopBubble(e){
       if(e&&e.stopPropagation){
              e.stopPropagation();
              }else{
                     window.event.cancelBubble=true;
                     }
       }
function $(id){return document.getElementById(id);}
//mousedown时： 
if($("name").setCapture){//IE 
   $("name").setCapture(); 
} 
else if(window.captureEvents){//FF 
   window.captureEvents(Event.MOUSEMOVE|Event.MOUSEUP|Event.STARTSELECT); 
} 

//mouseUp时： 
if($("name").releaseCapture){ 
      $("name").releaseCapture(); 
} 
else if(window.releaseEvents){ 
      window.releaseEvents(Event.MOUSEMOVE|Event.MOUSEUP|Event.STARTSELECT); 
}

//asp
//request.servervariables("http_referer")


//js
document.referrer