這里是一個JavaScript中顯示倒計時的方法，從10一秒一秒地往下減直到計時結束（即0），代碼如下：

runCount(10);

function runCount(t){

if(t>0){

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

t–;

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

}else{

document.getElementById(‘shownum').innerHTML = ‘倒計時結束！';

}

}

運行該js代碼前，需要先添加一個id為shownum的div。

js實現動態倒計時功能 * a是從后臺接收到的時間戳，需轉換成毫秒單位

<div>

距明年還有:

<span id='daya'></span>天

<span id='hoursa'></span>小時

<span id='minua'></span>分

<span id='secoa'></span>秒

</div>

<script type="text/javascript">

/**

*

* copyright WE 2012.7

* js實現動態倒計時功能

* a是從后臺接收到的時間戳，需轉換成毫秒單位

*

*/

var a=12345678; //以毫秒為單位

function fomtime()

{

a=a-1000;

var b=new Date();

b.setTime(0);

var c=new Date();

c.setTime(a);

var day1=b.getDate(); //為方便調用，把天數、小時等單獨定義

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();

</script>

按天倒計時

HTML代碼1:

<Script Language="JavaScript">

<!-- Begin

var timedate= new Date("January 14,2006");

var times="研究生考試";

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>現在離2006年"+times+"還有: <font color=#ffffff><b>"+time +"</b></font> 天</font></li>");

// End -->

</Script>

HTML代碼2:

<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>

距某某開幕式還有 [<script language="JavaScript" type="text/javascript">djs()</script>] 天

精確到秒的javascript倒計時代碼

HTML代碼:

<form name="form1">

<div align="center" align="center">

<center>離2013年還有:<br>

<input type="textarea" name="left" size="35" style="text-align: center">

</center>

</div>

</form>

<script LANGUAGE="javascript">

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+'小時, '+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();

}

// -->

</script>

某某運動會，按時間提示不同的階段

HTML代碼:

<!--倒計時Javascript begin-->

<script language="JavaScript">

<!--

function DigitalTime1()

{

var deadline= new Date("08/13/2007") //開幕倒計時

var symbol="8月13日"

var now = new Date()

var diff = -480 - now.getTimezoneOffset() //是北京時間和當地時間的時間差

var leave = (deadline.getTime() - now.getTime()) + diff*60000

var day = Math.floor(leave / (1000 * 60 * 60 * 24))

var hour = Math.floor(leave / (1000*3600)) - (day * 24)

var minute = Math.floor(leave / (1000*60)) - (day * 24 *60) - (hour * 60)

var second = Math.floor(leave / (1000)) - (day * 24 *60*60) - (hour * 60 * 60) - (minute*60)

var deadline_2= new Date("08/13/2004") //開幕后計時

var symbol_2="8月13日"

var now_2 = new Date()

var diff_2 = -480 - now.getTimezoneOffset() //是北京時間和當地時間的時間差

var leave_2 = (now_2.getTime() - deadline_2.getTime()) + diff_2*60000

var day_2 = Math.floor(leave_2 / (1000 * 60 * 60 * 24))

var hour_2 = Math.floor(leave_2 / (1000*3600)) - (day_2 * 24)

var minute_2 = Math.floor(leave_2 / (1000*60)) - (day_2 * 24 *60) - (hour_2 * 60)

var second_2 = Math.floor(leave_2 / (1000)) - (day_2 * 24 *60*60) - (hour_2 * 60 * 60) - (minute_2*60)

day=day+1;

day_2=day_2+1;

if (day>0) //還未開幕

{

//LiveClock1.innerHTML = "現在"+symbol+"天"

LiveClock1.innerHTML = "<font

setTimeout("DigitalTime1()",1000)

}

if (day<0) //已經開幕

{

//LiveClock1.innerHTML = "現在離"+symbol+"還有"+day+"天"+hour+"小時"+minute+"分"+second +"秒"

LiveClock1.innerHTML = "<font

setTimeout("DigitalTime1()",1000)

}

if (day==0) //正在開幕

{

//LiveClock1.innerHTML = "現在"+symbol+"天"

LiveClock1.innerHTML = "<font

setTimeout("DigitalTime1()",1000)

}

if (day<0 & day_2>19) //某某運動會結束

{

//LiveClock1.innerHTML = "現在離"+symbol+"還有"+day+"天"+hour+"小時"+minute+"分"+second +"秒"

LiveClock1.innerHTML = "<font

setTimeout("DigitalTime1()",1000)

}

}

// -->

</script>

<!--倒計時Javascript end-->

<body onload=DigitalTime1()>

<div id= LiveClock1></div>

</body>

按小時倒計時

HTML代碼:

<SCRIPT LANGUAGE="JavaScript">

<!--

var maxtime = 60*60 //一個小時，按秒計算，自己調整!

function CountDown(){

if(maxtime>=0){

minutes = Math.floor(maxtime/60);

seconds = Math.floor(maxtime%60);

msg = "距離結束還有"+minutes+"分"+seconds+"秒";

document.all["timer"].innerHTML=msg;

if(maxtime == 5*60)

alert('注意，還有5分鐘!');

--maxtime;

}

else{

clearInterval(timer);

alert("時間到，結束!");

}

}

timer = setInterval("CountDown()",1000);

//-->

</SCRIPT>

<div id="timer" style="color:red"></div>

Javascript倒計時器 - 采用系統時間自校驗

這次利用系統時間自校驗倒計時, 無需手工調校使得倒計時更為精確, 代碼及詳細注釋如下:

<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">

var normalelapse = 100;

var nextelapse = normalelapse;

var counter;

var startTime;

var start = clock.innerText;

var finish = "00:00:00:00";

var timer = null;

// 開始運行

function run() {

startB.disabled = true;

endB.disabled = false;

counter = 0;

// 初始化開始時間

startTime = new Date().valueOf();

// nextelapse是定時時間, 初始時為100毫秒

// 注意setInterval函數: 時間逝去nextelapse(毫秒)后, onTimer才開始執行

timer = window.setInterval("onTimer()", nextelapse);

}

// 停止運行

function stop() {

startB.disabled = false;

endB.disabled = true;

window.clearTimeout(timer);

}

window.onload = function() {

endB.disabled = true;

};

// 倒計時函數

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;

// 清除上一次的定時器

window.clearInterval(timer);

// 自校驗系統時間得到時間差, 并由此得到下次所啟動的新定時器的時間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;

// 啟動新的定時器

timer = window.setInterval("onTimer()", nextelapse);

}

</script>

以上所述就是本文的全部內容了，希望大家能夠喜歡。