js屏蔽右击

<script language="javascript">

    if (window.Event){
        document.captureEvents(Event.MOUSEUP);
    }

    function nocontextmenu(){
        event.cancelBubble = true
        event.returnValue = false;
        return false;
    }

    function norightclick(e){
        if (window.Event){
           if (e.which == 2 || e.which == 3){
              return false;
          }
        }
        else{
            if (event.button == 2 || event.button == 3){
                event.cancelBubble = true
                event.returnValue = false;
                return false;
            }
        }
    }

    document.oncontextmenu = nocontextmenu; //对ie5.0以上
   // document.onmousedown = norightclick; //对其它浏览器火狐不支持
</script>