这里是一个JavaScript中显示倒计时的方法，从10一秒一秒地往下减直到计时结束(即0)，代码如下：

runCount(10);

function runCount(t){

if(t>0){

document.getElementById(‘shownum').innerHTML = t;

t–;

setTimeout(function(){runCount(t);},1000);

}else{

document.getElementById(‘shownum').innerHTML = ‘倒计时结束！';

}

}

运行该js代码前，需要先添加一个id为shownum的div。

js实现动态倒计时功能 * a是从后台接收到的时间戳，需转换成毫秒单位

/**

*

* copyright WE 2012.7

* js实现动态倒计时功能

* a是从后台接收到的时间戳，需转换成毫秒单位

*

*/

var a=12345678; //以毫秒为单位

function fomtime()

{

a=a-1000;

var b=new Date();

b.setTime(0);

var c=new Date();

c.setTime(a);

var day1=b.getDate(); //为方便调用，把天数、小时等单独定义

var hours1=b.getHours();

var minu1=b.getMinutes();

var seco1=b.getSeconds();

var day2=c.getDate();

var hours2=c.getHours();

var minu2=c.getMinutes();

var seco2=c.getSeconds();

var day=day2-day1;

var hours=hours2-hours1;

var minu=minu2-minu1;

var seco=seco2-seco1;

document.getElementById('daya').innerHTML=day;

document.getElementById('hoursa').innerHTML=hours;

document.getElementById('minua').innerHTML=minu;

document.getElementById('secoa').innerHTML=seco;

setTimeout("fomtime()",1000);

}

fomtime();

按天倒计时

HTML代码1:

HTML代码2:

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)

}

距某某开幕式还有 [] 天

精确到秒的javascript倒计时代码

HTML代码:

startclock()

var timerID = null;

var timerRunning = false;

function showtime() {

Today = new Date();

var NowHour = Today.getHours();

var NowMinute = Today.getMinutes();

var NowMonth = Today.getMonth();

var NowDate = Today.getDate();

var NowYear = Today.getYear();

var NowSecond = Today.getSeconds();

if (NowYear <2000)

NowYear=1900+NowYear;

Today = null;

Hourleft = 23 - NowHour

Minuteleft = 59 - NowMinute

Secondleft = 59 - NowSecond

Yearleft = 2009 - NowYear

Monthleft = 12 - NowMonth - 1

Dateleft = 31 - NowDate

if (Secondleft<0)

{

Secondleft=60+Secondleft;

Minuteleft=Minuteleft-1;

}

if (Minuteleft<0)

{

Minuteleft=60+Minuteleft;

Hourleft=Hourleft-1;

}

if (Hourleft<0)

{

Hourleft=24+Hourleft;

Dateleft=Dateleft-1;

}

if (Dateleft<0)

{

Dateleft=31+Dateleft;

Monthleft=Monthleft-1;

}

if (Monthleft<0)

{

Monthleft=12+Monthleft;

Yearleft=Yearleft-1;

}

Temp=Yearleft+'年, '+Monthleft+'月, '+Dateleft+'天, '+Hourleft+'小时, '+Minuteleft+'分, '+Secondleft+'秒'

document.form1.left.value=Temp;

timerID = setTimeout("showtime()",1000);

timerRunning = true;

}

var timerID = null;

var timerRunning = false;

function stopclock () {

if(timerRunning)

clearTimeout(timerID);

timerRunning = false;

}

function startclock () {

stopclock();

showtime();

}

// -->

某某运动会，按时间提示不同的阶段

HTML代码:

按小时倒计时

HTML代码:

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:

00:01:11:00

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);

}

以上所述就是本文的全部内容了，希望大家能够喜欢。