<!DOCTYPE html>
<html>
<head>
<title>focus2.html</title>
<meta name="keywords" content="keyword1,keyword2,keyword3">
<meta name="description" content="this is my page">
<meta name="content-type" content="text/html; charset=UTF-16">
<!--<link rel="stylesheet" type="text/css" href="./styles.css">-->
</head>
<body>
<table border="1">
<tr>
<td colspan="4" >学生信息</td>
</tr>
<tr>
<th>姓名</th>
<th>年龄</th>
<th colspan="2">电话</th>
</tr>
<tr>
<td onfocus="this.style.backgroundColor='#00f';" onblur="this.style.backgroundColor='#fff';">刘勇</td>
<td onfocus="this.style.backgroundColor='#00f';" onblur="this.style.backgroundColor='#fff';">20</td>
<td onfocus="this.style.backgroundColor='#00f';" onblur="this.style.backgroundColor='#fff';">0732-88756773</td>
</tr>
</table>
</body>
</html>
为什么获得焦点后颜色不会变呢 ,或者还是它根本没有获得焦点呀