JS简单实用的倒计时效果实现代码

<!DOCTYPE HTML> 
<html> 
<head> 
<meta charset="utf-8"> 
<title>倒计时</title> 
<meta name="Author" content=""> 
<meta name="Keywords" content=""> 
<meta name="Description" content=""> 
<style type="text/css"> 
*{ 
margin: 0; 
padding: 0; 
} 
ul,li{list-style: none;} 
#show_time{color: #f00;font-size: 24px;font-weight: bold;} 
</style> 
</head> 
<body> 
<div id="show_time">

</div> 
<script type="text/javascript"> 
function countdown(){ 
var show_time = document.getElementById("show_time"); 
endtime = new Date("12/31/2012 23:59:59");//结束时间 
today = new Date();//当前时间 
delta_T = endtime.getTime() - today.getTime();//时间间隔 
if(delta_T < 0){ 
clearInterval(auto); 
show_time.innerHTML = "倒计时已经结束"; 
} 
window.setTimeout(countdown,1000); 
total_days = delta_T/(24*60*60*1000);//总天数 
total_show = Math.floor(total_days);//实际显示的天数 
total_hours = (total_days - total_show)*24;//剩余小时 
hours_show = Math.floor(total_hours);//实际显示的小时数 
total_minutes = (total_hours - hours_show)*60;//剩余的分钟数 
minutes_show = Math.floor(total_minutes);//实际显示的分钟数 
total_seconds = (total_minutes - minutes_show)*60;//剩余的分钟数 
seconds_show = Math.floor(total_seconds);//实际显示的秒数 
show_time.innerHTML = "距离结束还有:" + total_show + "天" + hours_show + "时" + minutes_show + "分" + seconds_show + "秒"; 
} 
countdown(); 
</ script> 
</body> 
</html>

[Ctrl+A 全选注:如需引入外部Js需刷新才能执行]

JS简单实用的倒计时效果实现代码_javascript技巧