​x
 
<html>
<head>
<script type="text/javascript" src="/jquery/jquery.js"></script>
<script type="text/javascript">
$(document).ready(function(){
  $("input").select(function(){
    $("input").after(" Text marked!");
  });
});
</script>
</head>
<body>
<input type="text" name="FirstName" value="Hello World" />
<p>请试着选取输入域中的文本，看看会发生什么。</p>
</body>
</html>
​