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>

某某运动会，按时间提示不同的阶段

HTML代码:

<!--倒计时Javascript begin-->
<script language="JavaScript">
<!--
function DigitalTime1()
{
 var deadline= new Date("08/13/2007") //开幕倒计时
 var symbol="8月13日"
 var now = new Date()
 var diff = -480 - now.getTimezoneOffset() //是北京时间和当地时间的时间差
 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") //开幕后计时
 var symbol_2="8月13日"
 var now_2 = new Date()
 var diff_2 = -480 - now.getTimezoneOffset() //是北京时间和当地时间的时间差
 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) //还未开幕
 {
  //LiveClock1.innerHTML = "现在"+symbol+"天"
  LiveClock1.innerHTML = "<font
  setTimeout("DigitalTime1()",1000)
 } 

 if (day<0) //已经开幕
 {
  //LiveClock1.innerHTML = "现在离"+symbol+"还有"+day+"天"+hour+"小时"+minute+"分"+second +"秒"
  LiveClock1.innerHTML = "<font
  setTimeout("DigitalTime1()",1000)
 } 

 if (day==0) //正在开幕
 {
  //LiveClock1.innerHTML = "现在"+symbol+"天"
  LiveClock1.innerHTML = "<font
  setTimeout("DigitalTime1()",1000)
 } 

 if (day<0 & day_2>19) //某某运动会结束
 {
  //LiveClock1.innerHTML = "现在离"+symbol+"还有"+day+"天"+hour+"小时"+minute+"分"+second +"秒"
  LiveClock1.innerHTML = "<font
  setTimeout("DigitalTime1()",1000)
 } 

}
// -->
</script>
<!--倒计时Javascript end-->
<body onload=DigitalTime1()>
<div id= LiveClock1></div> 

</body>

按小时倒计时

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>

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">
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>

以上所述就是本文的全部内容了，希望大家能够喜欢。