Js monitors the closing refreshing backtracking and forward events of the Internet explorer firefox browser

2020-03-30 03:36:20
OfStack
<html>
  <head>
    <title>test</title>
      <script language ="javaScript">
        <!-- Close the browser  -->
        var flag = true;
        window.onbeforeunload = function () {
          if (flag) {
            var evt = window.event || arguments[0];
            var userAgent = navigator.userAgent;
            if (userAgent.indexOf("MSIE") > 0) {
              var n = window.event.screenX - window.screenLeft;
              var b = n > document.documentElement.scrollWidth - 20;
              if (b && window.event.clientY < 0 || window.event.altKey) {
                window.event.returnValue = (" This action will cause an abnormal exit from the system ( Correct way to exit the system: click the exit button ) Are you sure ?");
              }else {
                return (" This action will cause an abnormal exit from the system ( Correct way to exit the system: click the exit button ) Are you sure ?");
              }
            }else if (userAgent.indexOf("Firefox") > 0) {
               return (" This action will cause an abnormal exit from the system ( Correct way to exit the system: click the exit button ) Are you sure ?");
            }
          }
        }
     </script>
  </head>
  <body>
     dengyang
  <body>
</html>