JS倒计时代码

JS倒计时代码
HTML代码:  
<SCRIPT LANGUAGE="JavaScript">  
<!--  
var maxtime = 60*60 //一个小时，按秒计算，自己调整!  
function CountDown(){  
if(maxtime>=0){  
minutes = Math.floor(maxtime/60);  
seconds = Math.floor(maxtime%60);  
msg = "距离结束还有"+minutes+"分"+seconds+"秒";  
document.all["timer"].innerHTML=msg;  
if(maxtime == 5*60) alert('注意，还有5分钟!');  
--maxtime;  
}  
else{  
clearInterval(timer);  
alert("时间到，结束!");  
}  
}  
timer = setInterval("CountDown()",1000);  
//-->  
</SCRIPT>  
<div id="timer" style="color:red"></div>  






第四种：最简倒计时  



HTML代码:  
<Script Language="JavaScript">   
<!-- Begin   
　　var timedate= new Date("January 14,2006");   
　　var times="研究生考试";   
　　var now = new Date();   
　　var date = timedate.getTime() - now.getTime();   
　　var time = Math.floor(date / (1000 * 60 * 60 * 24));   
　　if (time >= 0) ;  
document.write("<li><font color=#DEDBDE>现在离2006年"+times+"还有: <font color=#ffffff><b>"+time +"</b></font> 天</font></li>");  
// End -->  
</Script>  






第五种：最简倒计时二  



HTML代码:  
<script language="JavaScript" type="text/javascript">  
function djs(){  
var urodz= new Date("11/12/2008");　  
var now = new Date();  
var num  
var ile = urodz.getTime() - now.getTime();　　  
var dni = Math.floor(ile / (1000 * 60 * 60 * 24));　　  
if (dni >1)　　  
num=dni+1
else if (dni == 1)　num=2　  
else if (dni == 0)　num=1
else num=0　  
document.write(num)　　  
}  
</script>  

距某某开幕式还有 [<script language="JavaScript" type="text/javascript">djs()</script>] 天  
第五个：Javascript倒计时器 - 采用系统时间自校验  
这次利用系统时间自校验倒计时, 无需手工调校使得倒计时更为精确, 代码及详细注释如下:  

<span id="clock">00:01:11:00</span>  
<input id="startB" type="button" value="start countdown!" onclick="run()">  
<input id="endB" type="button" value="stop countdown!" onclick="stop()">  
<br>  
<input id="diff" type="text">  
<input id="next" type="text">  
<script language="Javascript">  
/* This notice must be untouched at all times.

countdown.js    v. 1.0
The latest version is available at
http://blog.csdn.net/yjgx007

Copyright (c) 2004 Xinyi.Chen. All rights reserved.
Created 7/30/2004 by Xinyi.Chen.  
Web: http://blog.csdn.net/yjgx007
E-Mail: [e-mail]
Last modified: 7/30/2004

This program is free software;
you can redistribute it and/or modify it under the terms of the
GNU General Public License as published by the Free Software Foundation;

See the GNU General Public License
at http://www.gnu.org/copyleft/gpl.html for more details.
*/
var normalelapse = 100;  
var nextelapse = normalelapse;  
var counter;   
var startTime;  
var start = clock.innerText;   
var finish = "00:00:00:00";  
var timer = null;  

// 开始运行  
function run() {  
startB.disabled = true;  
endB.disabled = false;  
counter = 0;  
// 初始化开始时间  
startTime = new Date().valueOf();  

// nextelapse是定时时间, 初始时为100毫秒  
// 注意setInterval函数: 时间逝去nextelapse(毫秒)后, onTimer才开始执行  
timer = window.setInterval("onTimer()", nextelapse);   
}  

// 停止运行  
function stop() {  
startB.disabled = false;  
endB.disabled = true;  
window.clearTimeout(timer);  
}  

window.onload = function() {  
endB.disabled = true;  
}  

// 倒计时函数  
function onTimer()  
{  

if (start == finish)  
{  
window.clearInterval(timer);  
alert("time is up!");  
return;  
}  

var hms = new String(start).split(":");  
var ms = new Number(hms[3]);  
var s = new Number(hms[2]);  
var m = new Number(hms[1]);  
var h = new Number(hms[0]);  
    
ms -= 10;  
if (ms < 0)  
{  
ms = 90;  
s -= 1;  
if (s < 0)  
{  
    s = 59;  
    m -= 1;  
}  
    
if (m < 0)  
{  
    m = 59;  
    h -= 1;  
}  
}  

var ms = ms < 10 ? ("0" + ms) : ms;  
var ss = s < 10 ? ("0" + s) : s;  
var sm = m < 10 ? ("0" + m) : m;  
var sh = h < 10 ? ("0" + h) : h;  

start = sh + ":" + sm + ":" + ss + ":" + ms;  
clock.innerText = start;  

// 清除上一次的定时器  
window.clearInterval(timer);  

// 自校验系统时间得到时间差, 并由此得到下次所启动的新定时器的时间nextelapse  
counter++;   
var counterSecs = counter * 100;  
var elapseSecs = new Date().valueOf() - startTime;  
var diffSecs = counterSecs - elapseSecs;  
nextelapse = normalelapse + diffSecs;  
diff.value = counterSecs + "-" + elapseSecs + "=" + diffSecs;  
next.value = "nextelapse = " + nextelapse;  
if (nextelapse < 0) nextelapse = 0;  

// 启动新的定时器  
timer = window.setInterval("onTimer()", nextelapse);   
}  
</script>
第六种：在线考试javaScript倒计时

<script type="text/javascript">
/*
================== hi.baidu.com/coolinc ===
*/

var h=0; //设置考试时间(小时单位)
var m=0.1; //设置考试时间(分钟单位)
var timeShowId="timeshow"; //设置时间显示层ID
var TimeNum=h*60*60+m*60;
var timeStr;
function ChangeTime(){
TimeNum--;
if(TimeNum > 0){
timeStr=setTimeout("ChangeTime()",1000);
}
else{
document.form1.submit();
}
document.getElementById(timeShowId).innerHTML="在线考试系统提示你的时间还剩"+Math.floor(TimeNum/60)+"分"+TimeNum%60+"秒";
//window.status="在线考试系统提示你的时间还剩"+Math.floor(TimeNum/60)+"分"+TimeNum%60+"秒";
}
</script>
<body onLoad="ChangeTime()">
<div id="timeshow" style="position:absolute;left:1px;top:1px;width:250px;height:20px;line-height:20px;text-align:center;font-size:12px;color:#000;background-color:#CCC;border:1px solid #333;"></div>
<br />
<form action="NS_Exam_result.asp" method="post" name="form1" id="form1">
...做题
<input type="submit" name="Submit" value="交卷">
</form>
</body>