withTest // with (document) {} // with (Math) {}

 

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
 <head>
  <title> withTest </title>
  <meta charset="UTF-8">
  <meta name="Author" content="">
  <meta name="Keywords" content="">
  <meta name="Description" content="">
 </head>

 <body>
 <div id="alertRet"> </div>

    <script type="text/javascript">
self.alert=function(str){
    var ret=document.getElementById("alertRet");
    var element=document.createElement("div");
    element.append(str);
    ret.append(element);
};

 function withTest() {
   with (document) { //document的重复使用
    writeln("Hello,");
    writeln("it's a with keyword test!");
   }
   
   with (Math) { //Math的重复使用
    alert(random());
    alert(abs(-10));
   }
  }
  withTest();
    </script>
 </body>
</html>
0.6695177875356813
10
Hello, it's a with keyword test!

 

posted @ 2018-02-07 17:18  sky20080101  阅读(51)  评论(0)    收藏  举报