倒计时跳转界面

 1 <!DOCTYPE html>
 2 <html>
 3     <meta charset="utf-8" />
 4     <title>倒计时跳转界面</title>
 5 <head>    
 6 </head>
 7 <body>
 8  <p>
 9      <span id="timer"></span> 秒后自动返回
10      <a href="http://www.cnblogs.com/beiz/">直接跳转</a>
11  </p>
12 
13 <script language="javascript" type="text/javascript">
14 window.onload = function(){
15     var time = 3; //设置时间为几秒
16     var timer = document.getElementById('timer'); //获取ID为timer的对象
17     timer.innerHTML = time; //初始化显示秒数
18     time = time - 1;
19     var g = window.setInterval(function(){
20         if(time<0){
21             window.clearTimeout(g); //清除动画
22             window.location.href = 'http://www.cnblogs.com/beiz/'; //跳转到指定地址
23             //window.history.back(-1); //后退
24         } else {
25             showTime();
26         }
27     },1000);
28     //显示函数
29     function showTime(){
30         timer.innerHTML = time;
31         time--;
32     }
33 };
34 </script>
35 </body>
36 </html>