JavaScript 实现旋转木马轮播图的核心逻辑与代码解析

完整代码示例

<!DOCTYPE html>
<html lang="en">
<head>
 <meta charset="UTF-8">
 <title></title>
 <style>
  * {
   margin: 0;
   padding: 0;
   border: none;
   list-style: none;
  }

  img {
   vertical-align: top;
  }

  body {
   background-color: #000;
  }

  #slider {
   width: 1200px;
   height: 460px;
   margin: 100px auto;
   position: relative;
   /*background-color: red;*/
  }

  #slider li {
   position: absolute;
   left: 200px;
   top: 0;
  }

  #slider li img {
   width: 100%;
   height: 100%;
  }

  .slider_ctl_prev, .slider_ctl_next {
   width: 76px;
   height: 112px;
   position: absolute;
   top: 50%;
   margin-top: -56px;
   z-index: 99;
  }

  #slider_ctl {
   opacity: 0;
  }

  .slider_ctl_prev {
   background: url("images/prev.png") no-repeat;
   left: 0;
  }

  .slider_ctl_next {
   background: url("images/next.png") no-repeat;
   right: 0;
  }
 </style>
</head>
<body>
<div id="slider">
 <ul id="slider_main">
  <li><img src="images/slidepic1.jpg" alt=""></li>
  <li><img src="images/slidepic2.jpg" alt=""></li>
  <li><img src="images/slidepic3.jpg" alt=""></li>
  <li><img src="images/slidepic4.jpg" alt=""></li>
  <li><img src="images/slidepic5.jpg" alt=""></li>
 </ul>
 <div id="slider_ctl">
  <span class="slider_ctl_prev"></span>
  <span class="slider_ctl_next"></span>
 </div>
</div>
<script src="../00MyTools/MyTools.js"></script>
<script>
 window.addEventListener('load',function (ev) {
  // 1. 获取需要标签
  var slider = myTool.$('slider');
  var sliderMain = myTool.$('slider_main');
  var allLis = sliderMain.children;
  var sliderCtl = myTool.$('slider_ctl');

  // 2. 位置信息
  var jsonArr = [
   {"width":"400", "top":"20", "left":"50", "opacity":"0.2", "zIndex":"2"},
   {"width":"600", "top":"70", "left":"0", "opacity":"0.8", "zIndex":"3"},
   {"width":"800", "top":"100", "left":"200", "opacity":"1", "zIndex":"4"},
   {"width":"600", "top":"70", "left":"600", "opacity":"0.8", "zIndex":"3"},
   {"width":"400", "top":"20", "left":"750", "opacity":"0.2", "zIndex":"2"}
  ];
  // 将位置信息作用到图片上去
  for (var i = 0; i < jsonArr.length; i++) {
   myTool.slowMoving(allLis[i], jsonArr[i]);
  }
  // 3. 设置显示和隐藏
  slider.addEventListener('mouseover', function () {
   myTool.slowMoving(sliderCtl, {'opacity': 1});
  });

  slider.addEventListener('mouseout', function () {
   myTool.slowMoving(sliderCtl, {'opacity': 0});
  });

  // 4. 监听点击
  for (var j = 0; j < sliderCtl.children.length; j++) {
   var item = sliderCtl.children[j];
   item.addEventListener('click',function (evt) {
    if (this.className === 'slider_ctl_prev'){
     // 点击左边
     // 两种方式
     // 1. 改变数据影响标签 数据驱动界面
     // 2. 改变标签适应数据
     jsonArr.push(jsonArr.shift())
    }else{
     // 点击右边
     jsonArr.unshift(jsonArr.pop())
    }

    // 重新布局
    for (var i = 0; i < jsonArr.length; i++) {
     myTool.slowMoving(allLis[i], jsonArr[i]);
    }
   },false);
  }
 },false)
</script>
</body>
</html>