1 // 商品倒计时用一个定时器来写
 2 //type 是不同页面
 3 var timecountdown = {
 4     Secondms_jx: 60 * 1000,
 5     minutems_jx: 1000,
 6     h: 100,
 7     timehms: false
 8 };
 9 
10 timecountdown.updateEndTime = function(type) {
11     var _that = this;
12     $(".item-djx").each(function(i, el) {
13         if(!this.num){
14            var endTime = parseInt(this.getAttribute("endTime"));
15        }else{
16            var endTime=this.num;
17        }       
18         var key = parseInt(this.getAttribute("itemid"));
19 
20 
21         if (endTime < 0) {
22             return true; //跳过此次循环
23         } else {
24             endTime = endTime - 1000;
25         }
26         this.num=endTime;
27         _that.clock_jx(key, endTime, type);
28     });
29 
30     setTimeout(function() {
31         _that.updateEndTime(type);
32         if(!_that.timehms){
33             _that.hmstime();
34         }
35     }, 1000);
36 }
37 
38 timecountdown.clock_jx = function(key, diff, skin) {
39     var _that = this;
40 
41     if (diff <= 0) {
42         $("#leftTimeJx" + key).parent().hide();
43         $("#leftTimeJx" + key).parent().parent().find('.jx-ing').show();
44         $.post('/yunbuy/lottery', 'skin=' + skin + '&id=' + key, function(data) {
45             setTimeout(function() {
46                 $('#itemDjx' + key).remove();
47                 $('#win-list .item-db').eq(0).before(data.html);
48             }, 5000);
49         }, 'json');
50     } else {
51         var DifferSecond = Math.floor(diff / _that.Secondms_jx);
52         diff -= DifferSecond * _that.Secondms_jx;
53         var DifferMinute = Math.floor(diff / _that.minutems_jx);
54         diff -= DifferMinute * _that.minutems_jx;
55 
56         if (DifferSecond.toString().length < 2) DifferSecond = '0' + DifferSecond;
57         if (DifferMinute.toString().length < 2) DifferMinute = '0' + DifferMinute;
58 
59         var sTime = "";
60         sTime += "<span>" + DifferSecond + "</span><b>:</b>";
61         sTime += "<span>" + DifferMinute + "</span><b>:</b>";
62         sTime += "<span class='timeHm'>" + 99 + "</span>";
63         document.getElementById("leftTimeJx" + key).innerHTML = sTime; //显示倒计时信息
64     }
65 }
66 timecountdown.hmstime = function() {
67     //毫秒单独计时
68     var _that = this;
69 
70     clearInterval(_that.timehms);
71     _that.timehms = setInterval(function() {
72 
73         if (_that.h <= 0) _that.h = 100;
74         _that.h = parseInt(_that.h) - 1;
75         if (_that.h.toString().length < 1) _that.h = '00';
76         if (_that.h.toString().length == 1) _that.h = '0' + _that.h;
77         if (_that.h.toString().length > 2) _that.h = '99';
78         setTimeout(function() {
79            if ($('.timeHm').length == 0) {
80             clearInterval(_that.timehms);
81             _that.timehms=false; //此处一定要赋值，不然下次 再次开启 我用的这个值得判断 就会不准，虽然定时器清了，但是那个值一直存在，可以说是定时器id
82            };
83         }, 5000);
84 
85         $('.timeHm').html(_that.h)
86     }, 15);
87 }
88 
89 timecountdown.hmstime();
清空定时器之后 输出timehms  这个值一直存在 而且占用内存  
 
for(var i=0;i<10;i++){
    var a=setInterval("1",10);
    console.log(a);
}
这个定时器其实开了10个，但是只有最后一个有名字，能控制，其他都控制不了，而且清不掉，占用内存。
会看到 开多少个定时器，他的id 会越来愈大。占用内存，小心内存泄露。因此 商城 多个计算 最好用循环，一次定时器搞定
，一个方法里最好只开一个定时器，再开之前先清定时器。方式定时器过多，控制不过来
 
 
 
 
浏览器机制  定时器的假死状态
定时器有一个问题，就是当页面中开一个定时器，然后你没有关闭页面，继续浏览其他网页，过一会（几分钟）你在浏览这个定时器，这个定时器，在这期间是假死状态，就是不执行，你在返回来看到的估计就是定时器只进行了几秒。
解决方案：把后台传过来的时间段，转化为本地时间几点过期，然后一直判断是否到达本地时间即可，解决这个bug
// 商品倒计时用一个定时器来写
//type 是不同页面
var timecountdown = {
    hours_jx: 60 * 60 * 1000,
    Secondms_jx: 60 * 1000,
    minutems_jx: 1000,
    h: 100,
    timehms: false
};

timecountdown.updateEndTime = function(type) {
    var _that = this;
    $(".item-djx").each(function(i, el) {
        if(!this.num){
            var endTime = parseInt(this.getAttribute("endTime"))+new Date().getTime();
            this.num=endTime;
       }else{
           var endTime=this.num;
       }       
        var key = parseInt(this.getAttribute("itemid"));


        var duringtime=endTime-new Date().getTime();
        duringtime = duringtime - 1000;
        if (duringtime <= 0) {

            if(this.onoff){

                return true; //跳过此次循环
            }
            $("#leftTimeJx" + key).parent().hide();
            $("#leftTimeJx" + key).parent().parent().find('.jx-ing').show();
            $.post('/yunbuy/lottery', 'skin=' + type + '&id=' + key, function(data) {
                setTimeout(function() {
                    $('#itemDjx' + key).remove();
                    $('#win-list .item-db').eq(0).before(data.html);
                }, 5000);
            }, 'json');
            this.onoff=true;
        } else {
            _that.clock_jx(key,duringtime);
        }

    });

    setTimeout(function() {
        _that.updateEndTime(type);
    }, 1000);
}

timecountdown.clock_jx = function(key, diff, skin) {
    var _that = this;

        var Differhours = Math.floor(diff / _that.hours_jx);
        diff -= Differhours *  _that.hours_jx;
        var DifferSecond = Math.floor(diff / _that.Secondms_jx);
        diff -= DifferSecond * _that.Secondms_jx;
        var DifferMinute = Math.floor(diff / _that.minutems_jx);
        diff -= DifferMinute * _that.minutems_jx;

        if (Differhours.toString().length < 2) Differhours = '0' + Differhours;
        if (DifferSecond.toString().length < 2) DifferSecond = '0' + DifferSecond;
        if (DifferMinute.toString().length < 2) DifferMinute = '0' + DifferMinute;

        var sTime = "";
        if(Differhours!='00'){
            sTime += "<span>" + Differhours + "</span><b>:</b>";
        }
        sTime += "<span>" + DifferSecond + "</span><b>:</b>";
        sTime += "<span>" + DifferMinute + "</span><b>:</b>";
        sTime += "<span class='timeHm'>" + 99 + "</span>";
        document.getElementById("leftTimeJx" + key).innerHTML = sTime; //显示倒计时信息

}

timecountdown.updateEndTime();