obj.prop1 obj['prop2'] 

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

 <body>
<script type="text/javascript">
    var obj={
        prop1:'hello',
        prop2:'world',
    };

    alert(obj.prop1);//OK
    var str='prop2';
    alert(obj[str]);//OK
    alert(obj.str);//undefined
</script>
 </body>
</html>

 

posted @ 2017-12-25 14:48  sky20080101  阅读(54)  评论(0)    收藏  举报