<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8" /> <title>无标题文档</title> </head> <body> <style type="text/css"> body{ font:12px/1.5 arial;} div{ padding:2px;} input,textarea{ border:1px solid #888;} .focus{ border:1px solid #f00; background:#fcc;} </style> <form action="" method="post"> <fieldset> <legend>个人基本信息</legend> <div> <label for="username">名称:</label> <input id="username" type="text" value="名称" /> </div> <div> <label for="pass">密码:</label> <input id="pass" type="password" value="密码" /> </div> <div> <label for="msg">详细信息:</label> <textarea id="msg" rows="2" cols="20">详细信息</textarea> </div> </fieldset> </form> <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js"></script> <script> $(function () { $(":input").focus(function () { $(this).addClass("focus"); if ($(this).val() == this.defaultValue) { $(this).val(""); } }).blur(function () { $(this).removeClass("focus"); if ($(this).val() == '') { $(this).val(this.defaultValue); } }); }); </script> </body> </html>