基于javascript实现精确到毫秒的倒计时限时抢购

$(function(){
  function leftTime(){
    var endTime = new Date("2016/5/20,12:00:00");//结束时间
    var curTime = new Date();//当前时间
    var leftTime = parseInt((endTime.getTime() - curTime.getTime())/1000);//获得时间差
    //小时、分、秒需要取模运算
    var d = parseInt(leftTime/(606024));
    var h = parseInt(leftTime/(6060)%24);
    var m = parseInt(leftTime/60%60);
    var s = parseInt(leftTime%60);
    var ms = parseInt(((endTime.getTime() - curTime.getTime())/100)%10);
    var txt = "剩余"+d+"天"+h+"小时"+m+"分钟"+s+"."+ms+"秒";
    $(".left-time").text(txt);
    if(leftTime<=0){ $(".left-time").text("团购结束");}
  };
  leftTime();
  var set = setInterval(leftTime,100);
});