JS倒计时 代码

<div>
<span id="KSD">3</span>天
<span id="KSH">12</span>小时
<span id="KSM">39</span>分钟
<span id="KSS">25</span>秒
</div>

<script type="text/javascript">
function countDown(targetTime, callback) {
var t_timestamp = Date.parse(targetTime);
var s_timestamp = new Date();
c_timestamp = t_timestamp - s_timestamp; // 倒计时间戳
if (c_timestamp > 0) {
setTimeout(function callee() {
countdownTime(c_timestamp);
if (c_timestamp > 0) {
c_timestamp -= 1000;
setTimeout(callee, 1000);
}
}, 1);
}

// 计算倒计时间(天，小时，分钟，秒)，并传入回调函数，执行回调
function countdownTime(c_timestamp) {
var d, h, m, s;
c_timestamp = c_timestamp / 1000;

d = parseInt(c_timestamp / 3600 / 24, 10); // 天数
h = parseInt(c_timestamp / 3600 % 24, 10); // 小时
m = parseInt(c_timestamp % 3600 / 60, 10); // 分钟
s = parseInt(c_timestamp % 3600 % 60, 10); // 秒

if (typeof callback === 'function') {
callback(d, h, m, s);
}
}
};

var targetTime = '2013/11/12 00:00:00'; // 大于本地时间(假如本地时间为：2013/3/14 16:10:00)
countDown(targetTime, function(d, h, m, s) {

// 补零
for (var i = 0, len = arguments.length; i < len; i++) {
if (String(arguments[i]).length < 2) {
arguments[i] = '0' + arguments[i];
}
}
// dom操作
document.getElementById('KSD').innerHTML = h;
document.getElementById('KSH').innerHTML = h;
document.getElementById('KSM').innerHTML = m;
document.getElementById('KSS').innerHTML = s;
});
</script>