倒计时

1、10分钟倒计时

var time;
        var djs = document.getElementById("djs");
        // var h = 23;
        var m = 10;
        var s = 00;
        time = setInterval(run, 1000);
            //进行倒计时显示  
        function run() {
            //停止计时器
            if (s == 0 && m == 0) {
                clearInterval(time);
                return false;
            }
            --s;
            if (s < 0) {
                --m;
                s = 59;
            }           
            djs.innerHTML = (m < 10 ? "0" + m : m) + ":" + (s < 10 ? "0" + s : s);
        }

2、倒计时到哪一天的哪一时间

function leftTimer(year,month,day,hour,minute,second){ 
   var leftTime = (new Date(year,month-1,day,hour,minute,second)) - (new Date()); //计算剩余的毫秒数 
   var days = parseInt(leftTime / 1000 / 60 / 60 / 24 , 10); //计算剩余的天数 
   var hours = parseInt(leftTime / 1000 / 60 / 60 % 24 , 10); //计算剩余的小时 
   var minutes = parseInt(leftTime / 1000 / 60 % 60, 10);//计算剩余的分钟 
   var seconds = parseInt(leftTime / 1000 % 60, 10);//计算剩余的秒数 
   days = checkTime(days); 
   hours = checkTime(hours); 
   minutes = checkTime(minutes); 
   seconds = checkTime(seconds);
   
   var str = `
   <h2>开奖倒计时</h2>
         <span >${days}</span>天<span>${hours}</span>时<span>${minutes}</span>分<span>${seconds}</span>秒
  `;
   document.getElementById("djs").innerHTML = str;  
 } 
 setInterval("leftTimer(2019,8,1,0,0,0)",1000); 
 function checkTime(i){ //将0-9的数字前面加上0，例1变为01 
   if(i<10) 
   { 
     i = "0" + i; 
   } 
   return i; 
 }