js实现时分秒倒计时

 html部分 <div class="active_time" id="active_time"></div>

 //js部分 function countTime(value) {         //获取当前时间         var date = new Date();         var now = date.getTime();          //设置截止时间         var endDate = new Date("2019-7-22 00:00:00");         var end = endDate.getTime();         //时间差         var differTime = end - now;         //定义变量,h,m,s保存倒计时的时间         var h, m, s;         if (differTime >= 0) {             h = Math.floor(differTime / 1000 / 60 / 60);             m = Math.floor(differTime / 1000 / 60 % 60);             s = Math.floor(differTime / 1000 % 60);             h = h < 10 ? ("0" + h) : h;             m = m < 10 ? ("0" + m) : m;             s = s < 10 ? ("0" + s) : s;             var timeDom = "倒计时：" + h + "小时" +  m + "分" +  s + "秒";             $("#active_time").text(timeDom);             //递归调用函数所以是延时器不是定时器             setTimeout(function () {                 countTime(value)             }, 1000);         } else {             var timeDom ="00小时 00分 00秒";             $("#active_time").text(timeDom); }}

效果

文章来源: https://blog.csdn.net/Feast_aw/article/details/92673608