js学习笔记之日期倒计时(天,时,分,秒)

<!doctype html>
<html>
<head>
    <meta charset="utf-8">
    <title>JS实现倒计时(时、分,秒)</title>
    <script>
        function ShowCountDown(year,month,day,divname)
        {
            var now = new Date();
            var endDate = new Date(year, month, day);
            var leftTime=endDate.getTime()-now.getTime();
            var dd = parseInt(leftTime / 1000 / 60 / 60 / 24, 10);//计算剩余的天数
            var hh = parseInt(leftTime / 1000 / 60 / 60 % 24, 10);//计算剩余的小时数
            var mm = parseInt(leftTime / 1000 / 60 % 60, 10);//计算剩余的分钟数
            var ss = parseInt(leftTime / 1000 % 60, 10);//计算剩余的秒数
            dd = checkTime(dd);
            hh = checkTime(hh);
            mm = checkTime(mm);
            ss = checkTime(ss);//小于10的话加0
            var cc = document.getElementById(divname);
            cc.innerHTML = "距离" + year + "" + month + "" + day + "日还有:" + dd + "" + hh + "小时" + mm + "" + ss + "";
        }
        function checkTime(i)
        {
            if (i < 10) {
                i = "0" + i;
            }
            return i;
        }
        window.setInterval(function(){ShowCountDown(2020,11,11,'countdown');}, 1000);
    </script>
</head>
<body>
<div id="countdown"></div>
</body>
</html>
原文地址:https://www.cnblogs.com/nightstarsky/p/5661223.html