JavaScript记时秒杀功能

JavaScript倒计时秒杀功能
开发中遇到了需要实现活动秒杀功能界面：（伪代码）

var dt = new Date(), hour = dt.getHours(),date = dt.getDay();var end = new Date(dt.getYear(),dt,getMonth(),date,12) //活动结束时间var diff = end - dt;var timer = setInterval(function(){    if(dt > 0 && hour > 10){ //hour > 10 活动开始时间       //do something    }else{      //do something      clearInterval(timer);    }    diff -= 1000; //timer 1sec},1000)