时分秒倒计时的js实现

时分秒倒计时的js实现，如图：

闲话少说，直接上代码。

html代码：

<div id="timer" data-timer="20160628140203" style="font-size:20px">
    剩余天数：
    <span id="timer_d">0</span>天
    <span id="timer_h">0</span>时
    <span id="timer_m">0</span>分
    <span id="timer_s">0</span>秒
</div>

js代码：

timer('timer');//调用方法

//时分秒倒计时方法
function timer(eleId){
    var element=document.getElementById(eleId);
    if(element){
        endTimer=element.getAttribute('data-timer');
        var endTime=new Date(parseInt(endTimer.substr(0,4), 10),parseInt(endTimer.substr(4,2), 10),parseInt(endTimer.substr(6,2), 10),parseInt(endTimer.substr(8,2), 10),parseInt(endTimer.substr(10,2), 10),parseInt(endTimer.substr(12,2), 10));
        var endTimeMonth=endTime.getMonth()-1;
        endTime.setMonth(endTimeMonth);
        var ts = endTime - new Date();
        if(ts>0){
            var dd = parseInt(ts / 1000 / 60 / 60 / 24, 10);
            var hh = parseInt(ts / 1000 / 60 / 60 % 24, 10);
            var mm = parseInt(ts / 1000 / 60 % 60, 10);
            var ss = parseInt(ts / 1000 % 60, 10);
            dd = dd<10?("0" + dd):dd;   //天
            hh = hh<10?("0" + hh):hh;   //时
            mm = mm<10?("0" + mm):mm;   //分
            ss = ss<10?("0" + ss):ss;   //秒
            document.getElementById("timer_d").innerHTML=dd;
            document.getElementById("timer_h").innerHTML=hh;
            document.getElementById("timer_m").innerHTML=mm;
            document.getElementById("timer_s").innerHTML=ss;
            setTimeout(function(){timer(eleId);},1000);
        }else{
            document.getElementById("timer_d").innerHTML=0;
            document.getElementById("timer_h").innerHTML=0;
            document.getElementById("timer_m").innerHTML=0;
            document.getElementById("timer_s").innerHTML=0;
        }
    }
}

建议：点点滴滴，积少成多！