动态显示当前时间

js中利用定时器每隔1000毫秒显示一次（1000毫秒=1秒）：
 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 5 <title>输出当前日期</title>
 6 <style type="text/css">
 7 body{ font-size:30px;}
 8 </style>
 9 <script type="text/javascript">
10 window.onload=function(){
11     showTime();
12     };
13 function showTime(){
14   var myDate=new Date();
15   var Year=myDate.getFullYear();
16   var Month=myDate.getMonth()+1;
17   var Day=myDate.getDate();
18   var d=myDate.getDay();
19   var week=['星期日','星期一','星期二','星期三','星期四','星期五','星期六'];
20   var Wek=week[d];
21   var Hour=myDate.getHours();
22   var Minute=myDate.getMinutes();
23   var Second=myDate.getSeconds();
24   Day=checkTime(Day);
25   Hour=checkTime(Hour);
26   Minute=checkTime(Minute);
27   Second=checkTime(Second);
28   document.getElementById('text').innerHTML='今天是:'+Year+'年'+Month+'月'+Day+'日'+Wek+Hour+'时'+Minute+'分'+Second+'秒';
29 setTimeout(showTime,500)
30 }
31 //当时分秒位数小于两位时，以02格式显示
32   function checkTime(i){
33       
34     if(i<10)
35     {
36         i='0'+i;
37     }
38       return i;
39       }
40 
41 </script>
42 
43 </head>
44 
45 <body>
46 <div id="text"></div>
47 </body>
48 
49 </html>