js屏蔽右键代码

 <script type="text/javascript">
document.body.oncontextmenu=document.body.ondragstart= document.body.onselectstart=document.body.onbeforecopy=function(){return false;}
; document.body.onselect=document.body.oncopy=document.body.onmouseup=function(){document.selection.empty();}
;</script>