javascript 学习笔记(四) 倒计时程序代码

  首先看全部完整代码:

  

   [Ctrl+A 全选 注:如需引入外部Js需刷新才能执行]

  html部分代码:

  可在文本框中输入倒计时的时间,如果当前时间小于截止时间,则正常返回,反之,则返回距离截止日期到现在的时间

  

复制代码 代码如下:

  <p>

  <label for="deadline">截止日期</label>

  <input type="text" value="2011-06-11" id="deadline" />

  <input type="button" value="开始倒计时" onclick="window.setInterval('countDown(\'deadline\')', 1000)" />

  </p>

  <p id="showTime"></p>

  javascript部分代码:

  

复制代码 代码如下:

  function countDown(endDate) {

  var now = new Date();

  var deadtime = document.getElementById(endDate);

  var deadline = new Date(deadtime.value);

  //本地时间与格林威治标准时间 (GMT) 的分钟差

  var timeDiff = now.getTimezoneOffset();

  //此处有些不解,如果把分钟差转化成毫秒应该是timeDiff*60*1000,但是这样返回的数据不正确!

  var leave = Math.abs(deadline.getTime() - now.getTime() + timeDiff*60);

  var minute = 1000 * 60;

  var hour = minute * 60;

  var day = hour * 24;

  var countDay = Math.floor(leave/day);

  //var countHour = Math.floor((leave - day*countDay)/hour); 两种计算思路

  var countHour = Math.floor(leave/hour - countDay*24);

  var countMinute = Math.floor(leave/minute) - countDay*24*60 - countHour*60;

  var countSecond = Math.floor(leave/1000) - countDay*24*60*60 - countHour*60*60 - countMinute*60;

  var outStr = "";

  if(deadline < now) {

  outStr = "距离"+deadtime.value+"已有"+countDay+"天"+countHour+"小时"+countMinute+"分"+countSecond+"秒";

  } else {

  outStr = "距离"+deadtime.value+"还差"+countDay+"天"+countHour+"小时"+countMinute+"分"+countSecond+"秒";

  }

  var showTime = document.getElementById("showTime");

  showTime.innerHTML = outStr;

  }