js几秒以后倒计时跳转示例

代码如下:

 <html>
 <head>
 <title>出错啦~~~</title>
 <link href="css/login1.css" mce_href="css/login1.css" rel="stylesheet" type="text/css" />
 <script language="javascript" type="text/javascript">
 var i = ;
 var intervalid;
 intervalid = setInterval("fun()", );
 function fun() {
 if (i == ) {
 window.location.href = "../index.html";
 clearInterval(intervalid);
 }
 document.getElementById("mes").innerHTML = i;
 i--;
 }
 </script>
 </head>
 <body>
 <div id="errorfrm">
 <h3>出错啦~~~</h3>
 <div id="error">
 <img src="data:images/error.gif" mce_src="data:images/error.gif" alt="" />
 <p>系统出错，请联系管理员！</p>
 <p>将在 <span id="mes"></span> 秒钟后返回首页！</p>
 </div>

 </div>
 </body>
 </html>