jQuery 隐藏和显示 input 默认值

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 5 <title>jQuery+JavaScript 实现 table 的增加和减少</title>
 6 <script language="javascript" src="jquery-1.7.1.min.js"></script>
 7 </head>
 8 <body>
 9 <p><input type="text" value="请输入邮箱地址" id="email" id="email" /></p>
10 <p><input type="button" value="提交" /></p>
11 <script type="text/javascript">
12     $("#email").focus(function(){
13         var email_txt = $(this).val();
14         if (email_txt == this.defaultValue) {
15             $(this).val("");
16         }
17     })
18     $("#email").blur(function(){
19         var email_txt = $(this).val();
20         if (email_txt == "") {
21             $(this).val(this.defaultValue);
22         }
23     })
24 </script>
25 </body>
26 </html>

posted @ 2012-08-19 21:05  小2010  阅读(1404)  评论(0编辑  收藏  举报