jquery实现多个商品倒计时

html<pre>
<span endTime="1472169600" class="start_time"></span>
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jquery
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<script
function timer(){
window.setInterval(function(){
$('.start_time').each(function(i){//循环每一个类
console.log(this);
var start_time = $(this).attr("endTime"); //获得当前这个类中的结束时间戳 秒
var currentTime = new Date().getTime();//获得当前的时间戳 毫秒
var intDiff = start_time - Math.round(new Date().getTime()/1000-28800);//把当前时间戳毫秒级转换成秒级进行加减

              var day=0,
              hour=0,
              minute=0,
              second=0;//时间默认值        
              if(intDiff > 0){
                  day = Math.floor(intDiff / (60 * 60 * 24));
                  hour = Math.floor(intDiff / (60 * 60)) - (day * 24);
                  minute = Math.floor(intDiff / 60) - (day * 24 * 60) - (hour * 60);
                  second = Math.floor(intDiff) - (day * 24 * 60 * 60) - (hour * 60 * 60) - (minute * 60);
              }
              if (minute <= 9) minute = '0' + minute;
              if (second <= 9) second = '0' + second;
              $(this).html(day+"天"+hour+'时'+minute+'分'+second+'秒');//输出
              
            });
          }, 1000);//每一秒执行一次
      } 
      $(function(){
          timer();
      });    
      </script>

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