Javascript 洗牌几组横幅

我用它来旋转一些横幅，但问题是如果我有超过3个ou 4

vars

（横幅组），则

文档.getElementById

将停止工作

你知道为什么吗？或者有没有更好的方法

var banner = [
["destination1.com", "https://via.placeholder.com/468x60?text=468x60+Full", "alt Title 1", "event label 1"],
["destination2.com", "https://via.placeholder.com/728x90?text=728x90+Leaderboard", "alt Title 2", "event label 2"]
];

function shuffle(a) {
    var j, x, i;
    for (i = a.length - 1; i > 0; i--) {
        j = Math.floor(Math.random() * (i + 1));
        x = a[i];
        a[i] = a[j];
        a[j] = x;
    }
    return a;
}

shuffle(banner);
document.getElementById('vidmob').innerHTML = '<a href="'+banner[0][0]+'" target="_blank" rel="nofollow"><img src="'+bannervideosmob[0][1]+'" style="z-index:5;border:none" alt="'+banner[0][2]+'" onClick="gtag(\'event\', \'Click\', {\'event_category\': \'ads\',\'event_label\': \'mob-'+banner[0][3]+'\'});" /></a>';

var横幅=[
[“destination1.com”https://via.placeholder.com/468x60?text=468x60+“完整”、“替换标题1”、“事件标签1”]，
[“destination2.com”https://via.placeholder.com/728x90?text=728x90+排行榜”、“备选标题2”、“活动标签2”]
];
函数洗牌（a）{
变量j，x，i；
对于（i=a.length-1；i>0；i--）{
j=数学地板（数学随机（）*（i+1））；
x=a[i]；
a[i]=a[j]；
a[j]=x；
}
返回a；
}
洗牌（横幅）；
document.getElementById（'vidmob'）。innerHTML=''；

不使用3个或更多横幅的实施示例：

var banner = [
["destination1.com", "https://via.placeholder.com/468x60?text=468x60+Full", "alt Title 1", "event label 1"],
["destination2.com", "https://via.placeholder.com/728x90?text=728x90+Leaderboard", "alt Title 2", "event label 2"]
];
var banner1 = [
["destination3.com", "https://via.placeholder.com/300x250?text=300x250+MPU", "alt Title 3", "event label 3"],
["destination4.com", "https://via.placeholder.com/120x600?text=120x600+Skyscraper", "alt Title 4", "event label 4"]
];
var banner2 = [
["destination5.com", "https://via.placeholder.com/160x600?text=160x600+Wide+Skyscaper", "alt Title 5", "event label 5"],
["destination6.com", "https://via.placeholder.com/300x600?text=300x600+Half+Page+Ad", "alt Title 6", "event label 6"]
];
var banner3 = [
["destination7.com", "https://via.placeholder.com/125x125?text=125x125+Square+Button", "alt Title 7", "event label 7"],
["destination8.com", "https://via.placeholder.com/234x60?text=234x60+Half+Banner", "alt Title 8", "event label 8"]
];


function shuffle(a) {
    var j, x, i;
    for (i = a.length - 1; i > 0; i--) {
        j = Math.floor(Math.random() * (i + 1));
        x = a[i];
        a[i] = a[j];
        a[j] = x;
    }
    return a;
}

shuffle(banner);
document.getElementById('divid1').innerHTML = '<a href="'+banner[0][0]+'" target="_blank" rel="nofollow"><img src="'+banner[0][1]+'" style="z-index:5;border:none" alt="'+banner[0][2]+'" onClick="gtag(\'event\', \'Click\', {\'event_category\': \'ads\',\'event_label\': \'mob-'+banner[0][3]+'\'});" /></a>';

shuffle(banner1);
document.getElementById('divid2').innerHTML = '<a href="'+banner1[0][0]+'" target="_blank" rel="nofollow"><img src="'+banner1[0][1]+'" style="z-index:5;border:none" alt="'+banner1[0][2]+'" onClick="gtag(\'event\', \'Click\', {\'event_category\': \'ads\',\'event_label\': \'mob-'+banner1[0][3]+'\'});" /></a>';

shuffle(banner2);
document.getElementById('divid3').innerHTML = '<a href="'+banner2[0][0]+'" target="_blank" rel="nofollow"><img src="'+banner2[0][1]+'" style="z-index:5;border:none" alt="'+banner2[0][2]+'" onClick="gtag(\'event\', \'Click\', {\'event_category\': \'ads\',\'event_label\': \'mob-'+banner2[0][3]+'\'});" /></a>';

shuffle(banner3);
document.getElementById('divid4').innerHTML = '<a href="'+banner3[0][0]+'" target="_blank" rel="nofollow"><img src="'+banner3[0][1]+'" style="z-index:5;border:none" alt="'+banner3[0][2]+'" onClick="gtag(\'event\', \'Click\', {\'event_category\': \'ads\',\'event_label\': \'mob-'+banner3[0][3]+'\'});" /></a>';

var横幅=[
[“destination1.com”https://via.placeholder.com/468x60?text=468x60+“完整”、“替换标题1”、“事件标签1”]，
[“destination2.com”https://via.placeholder.com/728x90?text=728x90+排行榜”、“备选标题2”、“活动标签2”]
];
变量1=[
[“destination3.com”https://via.placeholder.com/300x250?text=300x250+“MPU”、“alt Title 3”、“事件标签3”]，
[“destination4.com”https://via.placeholder.com/120x600?text=120x600+“摩天大楼”、“备选标题4”、“活动标签4”]
];
变量2=[
[“destination5.com”https://via.placeholder.com/160x600?text=160x600+宽+Skyscape”、“alt Title 5”、“事件标签5”]，
[“destination6.com”https://via.placeholder.com/300x600?text=300x600+半页+页面+广告”、“alt Title 6”、“事件标签6”]
];
var banner3=[
[“destination7.com”https://via.placeholder.com/125x125?text=125x125+方形+按钮、“alt Title 7”、“事件标签7”]，
[“destination8.com”https://via.placeholder.com/234x60?text=234x60+“半+横幅”、“alt Title 8”、“事件标签8”]
];
函数洗牌（a）{
变量j，x，i；
对于（i=a.length-1；i>0；i--）{
j=数学地板（数学随机（）*（i+1））；
x=a[i]；
a[i]=a[j]；
a[j]=x；
}
返回a；
}
洗牌（横幅）；
document.getElementById（'divid1'）。innerHTML=''；
洗牌（横幅1）；
document.getElementById（'divid2'）。innerHTML=''；
洗牌（横幅2）；
document.getElementById（'divid3'）。innerHTML=''；
洗牌（横幅3）；
document.getElementById（'divid4'）。innerHTML=''；

我这样称呼他们：

<div class="mob" id="banner"></div>
<div class="mob" id="banner1"></div>
<div class="mob" id="banner2"></div>
<div class="mob" id="banner3"></div>
<div class="mob" id="banner4"></div>

用那些“dividX”显示您的HTML代码。@MajdJamal刚刚更新了te问题，谢谢！您似乎没有id名为“divid4”的div。@MajdJamal问题已编辑。。。但这不是问题所在。