基于javascript实现移动端轮播图效果

<!-- 结构 -->
  <!-- li*6>a[href=#]>img[src=./images/$.jpg] -->
  <div class="box">
    <ul>
      <!-- 为了无缝连接，我们在图片这里前后增加了2个图片 -->
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/6.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/1.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/2.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/3.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/4.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/5.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/6.jpg" alt=""></a>
      </li>
      <li>
        <a href="#" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" rel="external nofollow" ><img src="./images/1.jpg" alt=""></a>
      </li>
    </ul>
</div>

 * {
      margin: 0;
      padding: 0;
    }
    
    ul {
      list-style: none;
    }
    
    .box {
      width: 100%;
      overflow: hidden;
    }
    
    ul {
      /* 把li变成8张之后，需要，把ul的宽度变宽 */
      width: 800%;
      /* transition: all 1s; */
    }
    
    li {
      float: left;
      width: 12.5%;
    }
    
    img {
      width: 100%;
    }

//获取DOM
  var box = $(".box");
  var img = $("ul img");
  var ul = $("ul");
  var imgWidth = img.width();

  var index = 1;
  var right = index * imgWidth;
  ul.css("transform", `translateX(-${right}px)`);
  setTimeout(function() {
    ul.css("transition", "all 500ms");
  }, 100);

  //往左滑，坐标在增大
  box.on("swipeLeft", function() {
    index++;
    // if (index == img.length) {
    //   index = 0;
    // }
    var left = index * imgWidth;
    ul.css("transform", `translateX(-${left}px)`);
  });
  //往左滑，坐标在增大
  box.on("swipeRight", function() {
    index--;
    // if (index == -1) {
    //   index = img.length - 1;
    // }
    var right = index * imgWidth;
    ul.css("transform", `translateX(-${right}px)`);
  });

  //过渡结束之后时进行
  ul.on("transitionend", function() {
    //1.判读 index
    //往左面滑(滑倒倒数第一张的时候，其实显示的已经是用户想看的第一张)
    if (index == img.length - 1) {

      index = 1;
      //index修改完毕之后需要重新执行一遍
      var right = index * imgWidth;
      ul.css("transform", `translateX(-${right}px)`);

      //2.取消过渡效果
      ul.css("transition", "none");
      //3.已经判断完毕了，重新打开过渡效果
      //这里设置一个1毫秒的延迟，否则会一起进行
      setTimeout(function() {
        ul.css("transition", "all 500ms");
      }, 1);
    }

    //1.判读 index
    //往右面滑(滑倒index为0的时候，显示的是客户想看的第6张图)
    if (index == 0) {
      //2.取消过渡效果
      ul.css("transition", "none");
      index = img.length - 2;
      //index修改完毕之后需要重新执行一遍
      var left = index * imgWidth;
      ul.css("transform", `translateX(-${left}px)`);
      //延迟开启过渡效果
      setTimeout(function() {
        ul.css("transition", "all 500ms");
      }, 1)
    }
  })