倒计时在运营活动中很常见，这里记录一下
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<title>倒计时</title>
</head>
<body>
<div class="time"> <span id="LeftTime"></span></div>
</div>
<script>
function FreshTime()
{
var endtime=new Date("2015/11/20,12:20:12");//结束时间
var nowtime = new Date();//当前时间
var lefttime=parseInt((endtime.getTime()-nowtime.getTime())/1000);
d=parseInt(lefttime/3600/24);
h=parseInt((lefttime/3600)%24);
m=parseInt((lefttime/60)%60);
s=parseInt(lefttime%60);
document.getElementById("LeftTime").innerHTML="还剩" + d+"天"+h+"小时"+m+"分"+s+"秒";
if(lefttime<=0){
document.getElementById("LeftTime").innerHTML="开始抢购";
clearInterval(sh);
}
}
var sh;
sh=setInterval(FreshTime,1000);
</script>
</body>
</html>
