如下所示;
<!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>
<script type="text/javascript">
function change_bg(obj)
{
var a=document.getElementById("Menu").getElementsByTagName("a");
for(var i=0;i<a.length;i++)
{
a[i].className="";
}
obj.className="current";
}
</script>
<style type="text/css">
body{
font-size:17px;
}
.current{
background:red;
}
#container ul
{
list-style-type:none;
}
#container ul li
{
float:left;
margin-right:3px;
}
#container ul li a{
text-decoration:none;
color:#000;
}
</style>
</head>
<body>
<div id="container">
<ul id="Menu">
<li><a href="javascript:" onclick="change_bg(this)" class="current">Menu1</a></li>
<li><a href="javascript:" onclick="change_bg(this)">Menu2</a></li>
<li><a href="javascript:" onclick="change_bg(this)">Menu3</a></li>
<li><a href="javascript:" onclick="change_bg(this)">Menu4</a></li>
<li><a href="javascript:" onclick="change_bg(this)">Menu5</a></li>
</ul>
</div>
</body>
</html>