JS小整理

$(document).ready(
    function() {
　　　　 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();
       };
});