<!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"><body>
<table width="579" border="1" cellpadding="0" cellspacing="0" id=my_tab>
<tr>
<td width="127" height="25"> </td>
<td id="duihua" width="113" height="25" background="bt1.gif">aaa </td>
<td id="xinxi" width="113" height="25" background="bt2.gif">bbb </td>
<td id="guiji" width="113" height="25" background="bt2.gif">ccc </td>
<td id="tongji" width="113" height="25" background="bt2.gif">ddd </td>
</tr>
</table>
<script language="javascript">
<!--
function resetBG(){
var obj=document.getElementById("my_tab").cells;
for (var i=1;i<obj.length;i++){
obj[i].background="bt2.gif"
}
}
onload=function(){
var obj=document.getElementById("my_tab").cells
for (var i=1;i<obj.length;i++)
obj[i].onclick=function(){resetBG();this.background="bt1.gif"}
}
//-->
</script>
</body>
<head >
<title>无标题页</title>
</head>
<body>
<table width="579" border="1" cellpadding="0" cellspacing="0">
<tr >
<td width="127" height="25" > </td>
<td id="duihua" width="113" height="25" style="background-image:url(./bt1.gif)" onclick="changebg(this)">aaa </td>
<td id="xinxi" width="113" height="25" style="background-image:url(./bt2.gif)" onclick="changebg(this)">bbb </td>
<td id="guiji" width="113" height="25" style="background-image:url(./bt2.gif)" onclick="changebg(this)">ccc </td>
<td id="tongji" width="113" height="25" style="background-image:url(./bt2.gif)" onclick="changebg(this)">ddd </td>
</tr>
</table>
</body>
</html>
<script>
function changebg(obj)
{
var al=['duihua','xinxi','guiji','tongji'];
for(var i=0;i<al.length;i++)
{
if(al[i]!=obj.id)
document.getElementById(al[i]).style.background ='url(./bt2.gif)';
}
obj.style.background ='url(./bt1.gif)';
}</script>