简单js倒计时代码，到时间后显示已经结束！
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title></title>
<style type="text/css">
.HotDate{height: 50px;width: 250px;margin: 2px auto;background: #666666;
}
.HotDate span{display: inline-block;padding: 4px;background: #fff;color: #000;font-size: 16px;}
</style>
</head>
<DIV id="CountMsg" class="HotDate">
<span id="t_d">00</span>天
<span id="t_h">00</span>时
<span id="t_m">00</span>分
<span id="t_s">00</span>秒
</DIV>
<script type="text/javascript">
function getRTime(){
var EndTime= new Date('2015/11/21 10:30:00');
var NowTime = new Date();
var t =EndTime.getTime() - NowTime.getTime();
if(t < 0){
clearInterval(time1);
document.getElementById("CountMsg").innerHTML = "活动已经结束";
}{
var d=Math.floor(t/1000/60/60/24);
var h=Math.floor(t/1000/60/60%24);
var m=Math.floor(t/1000/60%60);
var s=Math.floor(t/1000%60);
document.getElementById("t_d").innerHTML = (d<10?'0':'') +d ;
document.getElementById("t_h").innerHTML = (h<10?'0':'') +h ;
document.getElementById("t_m").innerHTML = (m<10?'0':'') +m ;
document.getElementById("t_s").innerHTML = (s<10?'0':'') +s ;
}
}
var time1 = setInterval(getRTime,1000);
</script>
</body>
</html>
