js 倒计时

/*倒计时部分*/  var time = 1470123481576;  //时间戳  ShowCountDown(time);  function ShowCountDown(time) {    var now = new Date();    var leftTime=time-now.getTime();    var leftsecond = parseInt(leftTime/1000);    //var day1=parseInt(leftsecond/(24*60*60*6));    var day1=Math.floor(leftsecond/(60*60*24));    var hour=Math.floor((leftsecond-day1*24*60*60)/3600);    var minute=Math.floor((leftsecond-day1*24*60*60-hour*3600)/60);    /*var second=Math.floor(leftsecond-day1*24*60*60-hour*3600-minute*60);*/    var dd1 = parseInt(day1/10);    var dd2 = parseInt(day1%10);    var hh1 = parseInt(hour/10);    var hh2 = parseInt(hour%10);    var mm1 = parseInt(minute/10);    var mm2 = parseInt(minute%10);    /*var ss1 = parseInt(second/10);    var ss2 = parseInt(second%10);*/    var cc = document.getElementById('countdown');    cc.innerHTML = '倒计时<div class="v-fcm">'+dd1+'</div><div class="v-fcm">'+dd2+'</div>天<div>'+hh1+'</div><div>'+hh2+'</div>时<div>'+mm1+'</div><div>'+mm2+'</div>分';    //测试代码 ↓    /*cc.innerHTML = '倒计时<div class="v-fcm">'+dd1+'</div><div class="v-fcm">'+dd2+'</div>天<div>'+hh1+'</div><div>'+hh2+'</div>时<div>'+mm1+'</div><div>'+mm2+'</div>分<div class="v-fcm">'+ss1+'</div><div class="v-fcm">'+ss2+'</div>秒';*/    /*根据条件判断是否有必要继续启动下一个定时器*/    if(leftTime>=1000){      timer=setTimeout('ShowCountDown(time)',1000);    }else{//如果不满足继续的条件，就清除timer      timer=null;    }  }