js倒计时简单实现代码

<div id="clock">  <span id="days"></span>天  <span id="hours"></span>时  <span id="minutes"></span>分  <span id="seconds"></span>秒</div>

<script><br>/*计算剩余时间*/  function getTimeReamin(endtime){   //剩余的秒数    var remainSec=(Date.parse(endtime)-Date.parse(new Date()))/1000;    var days=Math.floor(remainSec/(3600*24));    var hours=Math.floor(remainSec/3600%24);    var minutes=Math.floor(remainSec/60%60);    var seconds=Math.floor(remainSec%60);    return{"remainSec":remainSec,     "days":days,     "hours":hours,     "minutes":minutes,     "seconds":seconds    }  } var endtime="2016/10/10";var clock=document.getElementById("clock");//设置定时器var timeid=setInterval(function () {  var t=getTimeReamin(endtime);  //判断时间格式  days= t.days>=0&& t.days<10?"0"+t.days:t.days;  hours= t.hours>=0&& t.hours<10?"0"+t.hours:t.hours;  minutes=t.minutes>=0&&t.minutes<10?"0"+t.minutes:t.minutes;  seconds=t.seconds>=0&&t.seconds<10?"0"+t.seconds:t.seconds;  //设置时间  document.getElementById("days").innerText= days;  document.getElementById("hours").innerText= hours;  document.getElementById("minutes").innerText= minutes;  document.getElementById("seconds").innerText=seconds;　　//清除定时器  if(t.remainSec<=0){    clearInterval(timeid);  }});<script>