一. 需求：左边是内容板块，右边是目录结构，点击右边内容跳转到左边相应位置展示，滑动左边内容右边目录自动跳转。 

 二、实现：

1. 左边每一个内容模块都给一个ref和应该相同的class类名，方便获取dom；
2. 左边内容区域使用滑动事件@scroll="handleScroll"，内容区域滑动即触发该方法；
3. 右边使用点击事件@click="goAnchor('anchor-' + index, index)"获取当前点击的dom；

• handleScroll()  滚动监听方法实现滑动左边内容对应上右边目录

•  goAnchor() 右边锚点选中跳转相应内容区域，通过scrollIntoView({ behavior: 'smooth' })平滑跳转

  3.代码：

<template>
  <div class="panel-block flex">
    <div class="panel-left" ref="anchorRef" @scroll="handleScroll">
      <div class="panel-item anchor-item" ref="anchor-0">
        <div class="panel-item-title">内容区域1</div>
        xxx
      </div>
     <div class="panel-item anchor-item" ref="anchor-1">
        <div class="panel-item-title">内容区域2</div>
        xxx
      </div>
      <div class="panel-item anchor-item" ref="anchor-2">
        <div class="panel-item-title">内容区域3</div>
        <div class="panel-item-content">
         xxx
        </div>
      </div>
      <div class="panel-item anchor-item" ref="anchor-3">
        <div class="panel-item-title">内容区域4</div>
        <div class="panel-item-content">
         xxx
        </div>
      </div>
    </div>
    <div class="panel-right">
      <div class="step-line"></div>
      <ul class="step-ul">
        <li
          class="flex_align_item_center"
          v-for="(item, index) in stepData"
          :key="index"
          :class="{ 'step-active': activeBtn == index }"
          @click="goAnchor('anchor-' + index, index)"
        >
          <div class="step-icon"></div>
          <div class="step-label">{{ item }}</div>
        </li>
      </ul>
    </div>
  </div>
</template>

<script>
export default {
  data() {
    return {
      activeBtn: 0, //锚点按钮
      stepData: ['区域1', '区域2', '区域3', '区域4'],
      contentDiv: null, //锚点区域
    }
  },
  methods: {
    //锚点跳转
    goAnchor(selector, index) {
      this.activeBtn = index
      this.$refs[selector].scrollIntoView({ behavior: 'smooth' })
    },
    // 滚动监听器
    handleScroll(i) {
      // 获取所有锚点元素
      const navContents = document.querySelectorAll('.anchor-item')
      // 所有锚点元素的 offsetTop
      const offsetTopArr = []
      navContents.forEach((item) => {
        offsetTopArr.push(item.offsetTop)
      })
      // 获取当前文档流的 scrollTop
      const scrollTop = this.$refs.anchorRef.scrollTop
      offsetTopArr.forEach((item, index) => {
        if (scrollTop >= item) {
          this.activeBtn = index
        }
      })
    },
  }
}
</script>

-----------------以下为样式代码----------------------
<style lang="scss" scoped>
.panel-block {
    height: 100%;
    .panel-left {
      width: calc(100% - 180px);
      overflow-y: auto;
      height: 100%;
      .panel-item {
        .panel-item-content {
          padding: 10px;
          border-top: 0;
          min-height: 40px;
          .table-params {
            .table-header {
              height: 40px;
              line-height: 40px;
              width: 100%;
              border: 1px solid #ebeef5;
              border-bottom: none;
              background: #f5f7fa;
              font-weight: 700;
              font-size: 14px;
              color: #303133;
              padding-left: 15px;
            }
            .table-body-type {
              height: 32px;
              line-height: 32px;
              width: 100%;
              border: 1px solid #ebeef5;
              border-bottom: none;
              color: #303133;
              padding-left: 15px;
              .type-title {
                font-weight: 700;
                font-size: 12px;
              }
            }
          }
        }
      }
    }
    .panel-right {
      padding-top: 10px;
      position: fixed;
      left: calc(100% - 210px);
      .step-line {
        position: absolute;
        left: 6px;
        top: 0;
        width: 1px;
        background: #dcdfe6;
        height: calc(50vh - 85px);
        z-index: 0;
      }
      .step-ul {
        li {
          padding-bottom: 20px;
          .step-icon {
            width: 13px;
            height: 13px;
            margin-right: 20px;
            border-radius: 50%;
            z-index: 1;
          }
          .step-label {
            font-weight: 700;
            font-size: 14px;
            line-height: 22px;
            color: #303133;
          }
        }
        .step-active {
          .step-icon {
            border: 1px solid #1989fe;
            background: #fff;
          }
          .step-label {
            color: #1989fe;
          }
        }
      }
    }
    ::-webkit-scrollbar {
      width: 0 !important;
    }
  }
</style>