JavaScript 实现导航栏与楼层滚动联动效果

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
  <style>
    *{margin: 0;padding: 0;list-style: none;border:0;}
    html, body, ul{width: 100%;height: 100%;}
    #ul li{
      width: 100%;
      height: 100%;
      text-align: center;
      font-size: 30px;
      /*background-color: red;*/
      color: #fff;
    }

    #ol{
      width: 80px;
      background-color: #ccc;
      position: fixed;
      left: 50px;
      top: 200px;
      border: 1px solid #fff;
    }

    #ol li{
      text-align: center;
      line-height: 30px;
      border-bottom: 1px solid #fff;
      color: #fff;
      cursor: pointer;
    }

    #ol li.current{
      background-color: orangered;
    }
  </style>
</head>
<body>
  <!--导航-->
  <ol id="ol">
    <li class="current">第1层</li>
    <li>第2层</li>
    <li>第3层</li>
    <li>第4层</li>
    <li>第5层</li>
  </ol>
  <!--楼层-->
  <ul id="ul">
    <li>第1层内容</li>
    <li>第2层内容</li>
    <li>第3层内容</li>
    <li>第4层内容</li>
    <li>第5层内容</li>
  </ul>

<script src="../../00MyTools/MyTools.js"></script>
<script>
  window.addEventListener('load', function (ev) {
     // 1. 获取标签
    var ol = myTool.$('ol'), ul = myTool.$('ul');
    var ulLis = ul.children;
    var olLis = ol.children;

    // 是否是点击产生的滚动
    var isClick = false;

    // 2. 上色
    var colorArr = ['red', 'green', 'blue', 'purple', 'yellow'];
    for (var i = 0; i < colorArr.length; i++) {
      ulLis[i].style.backgroundColor = colorArr[i];
    }

    // 3. 监听导航点击
    for (var j = 0; j < olLis.length; j++) {
      var olLi = olLis[j];
      (function (index) {
        olLi.addEventListener('click', function () {
          isClick = true;
          for (var i = 0; i < olLis.length; i++) {
            olLis[i].className = '';
          }
          this.className = 'current';
          // document.documentElement.scrollTop = index * myTool.client().height;

          myTool.slowMoving(document.documentElement, {'scrollTop': index * myTool.client().height}, function () {
            isClick = false;
          });
        });
      })(j)
    }

    // 4. 监听滚动
    var roll = 0;
    window.addEventListener('scroll', function (ev1) {
      if(!isClick){
        // 4.1 获取头部滚动偏移的高度
        roll = Math.ceil(Number(myTool.scroll().top));

        // 4.2 遍历
        for (var i = 0; i < ulLis.length; i++) {
          // 4.3 判断
          if(roll >= ulLis[i].offsetTop){
            for (var j = 0; j < olLis.length; j++) {
              olLis[j].className = '';
            }
            olLis[i].className = 'current';
          }
        }
      }
    })
  });
</script>
</body>
</html>