<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xh ... [/quote]
[code] <!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=gb2312" />
<title>无标题文档</title>
<body>
</head>
<div >44444444</div>
<script type="text/javascript">
function $(str) {return document.getElementById(str);}
var i=1,sid,sid2
function s()
{
for(c=1;c<=4;c++)
{
sid = 'a'+i;
sid2 = 'a'+c;
if (sid2==sid)
{
$(sid2).style.display='block';
}
else
{
$(sid2).style.display='none';
}
}
if (i>=4)
{
i=1;
}
else
{
i++;
}
}
setInterval("s()",2000);
</script>