如何在动态元素上添加多个 类,一个数字递增?

How to add multiple classes, one with incrementing numbers, on a dynamic element?

我一直在尝试使用带有自定义 classes 的滑动滑块来创建一些幻灯片。

<!-- Swiper -->
<div class="swiper-container">
    <div class="swiper-wrapper">
        <div class="swiper-slide">Slide 1</div>
        <div class="swiper-slide">Slide 2</div>
        <div class="swiper-slide">Slide 3</div>
        <div class="swiper-slide">Slide 4</div>
        <div class="swiper-slide">Slide 5</div>
        <div class="swiper-slide">Slide 6</div>
        <div class="swiper-slide">Slide 7</div>
        <div class="swiper-slide">Slide 8</div>
        <div class="swiper-slide">Slide 9</div>
        <div class="swiper-slide">Slide 10</div>
    </div>
    <!-- Add Pagination -->
    <div class="swiper-pagination"></div>
</div>
<!-- Swiper JS -->
<script src="../dist/js/swiper.min.js"></script>
<!-- Initialize Swiper -->
<script>
var swiper = new Swiper('.swiper-container', {
    pagination: '.swiper-pagination',
    paginationClickable: true,
    paginationBulletRender: function (swiper, index, className) {
        return '<span class="' + className + '">' + (index + 1) + '</span>';
    }
});
</script>

滑动分页动态创建并生成

<span class="swiper-pagination-bullet">1</span>
<span class="swiper-pagination-bullet">2</span>
<span class="swiper-pagination-bullet">3</span>
<span class="swiper-pagination-bullet">4</span>
<span class="swiper-pagination-bullet">5</span>
<span class="swiper-pagination-bullet">6</span>

我想要 div class 刷卡分页到

<span class="swiper-pagination-bullet color-0">1</span>
<span class="swiper-pagination-bullet color-1">2</span>
<span class="swiper-pagination-bullet color-2">3</span>

如何添加 color-0、color-1、color-2 的额外自定义 class?非常感谢。

return '<span class="'+ className +' color-'+index+'" >'+(index+1)+'</span>';