var hourtime=prompt("输入下班时间，如下： ","17:30:00");

function displayTime() {

var elt = document.getElementById("clock");

var elt2 = document.getElementById("todaydatetime");

if(leftTime < 0)

{

elt.innerHTML = "Over";

}

else

{

//var endTime = new Date("2016/12/30 17:30:00");

var endTime =new Date(new Date().toLocaleDateString()+" "+hourtime);

var now = new Date();

var nowYear=now.getFullYear();

var nowMonth=now.getMonth()+1;

var nowDay=now.getDate();

var leftTime = endTime.getTime() - now.getTime();

var ms = parseInt(leftTime % 1000).toString();

leftTime = parseInt(leftTime / 1000);

var o = Math.floor(leftTime / 3600);

var d = Math.floor(o / 24);

var m = Math.floor(leftTime / 60 % 60);

var s = leftTime % 60;

elt2.innerHTML = nowYear + " 年 " + nowMonth + " 月 " + nowDay + " 日 ";

//elt.innerHTML = nowYear + " 年 " + nowMonth + " 月 " + nowDay + " 日 " + o + "小时:" + m + "分:" + s + "秒:" + ms.charAt(0);

elt.innerHTML =o + "小时:" + m + "分:" + s + "秒:" + ms.charAt(0);

setTimeout(displayTime, 100);

}

}

displayTime();

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