JavaScript实现简单的数字倒计时

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

<div>  距明年还有:  <span id='daya'></span>天  <span id='hoursa'></span>小时  <span id='minua'></span>分  <span id='secoa'></span>秒</div><script type="text/javascript">/****  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();</script>

按天倒计时

HTML代码1:

<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> 

HTML代码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> 

距某某开幕式还有 [<script language="JavaScript" type="text/javascript">djs()</script>] 天
精确到秒的javascript倒计时代码

HTML代码:

<form name="form1"> <div align="center" align="center"> <center>离2013年还有:<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();  } // --> </script>