用Asp.net屏蔽F5、Ctrl+N、Alt+F4 (收集)

<script language="javascript">
             function DisableKey()
              {
                     //8   退格键
                     //78  Ctrl+N
                     //37  Alt+ 方向键 ←
                     //39  Alt+ 方向键 →
                     //116       F5 刷新键
                     //82  Ctrl + R
                     //121       shift+F10
                     //115       屏蔽Alt+F4
                     //屏蔽 shift 加鼠标左键新开一网页
                     if (window.event.keyCode==8
                            ||event.keyCode==78
                            ||event.keyCode==37
                            ||event.keyCode==39
                            ||event.keyCode==116
                            ||event.keyCode==82
                            ||event.keyCode==121
                            ||event.keyCode==115
                            ||(window.event.srcElement.tagName == "A" && window.event.shiftKey))
                            {
                                   alert('请通过事物代码进行操作！');
                                   window.event.returnValue=false;
                            }
                     
              }
       </script>
       </HEAD>
       < body MS_POSITIONING="GridLayout" onKeyDown="DisableKey()">
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