<!DOCTYPE html>
<html>
<head>
</head>
<body><!--获取时间和秒并在页面上显示-->
<p></p>
<script>
window.onload=function(){showTime();}
function showTime()
{
var d=new Date();
var my=document.getElementsByTagName("p");
minute=d.getMinutes();
sec =d.getSeconds();
my[0].innerHTML=minute+":"+sec;
setTimeout(showTime,500);//注意此函数的学习
}
</script>
</body>
</html>
原文：http://www.cnblogs.com/zhzheng/p/5827183.html