//获取当前元素的offsetTop
  getOffsetTop(obj) {
   let offsetTop = 0;
   while (obj != window.document.body && obj != null) {
    offsetTop += obj.offsetTop;
    obj = obj.offsetParent;
   }
   return offsetTop;
  }

mounted() {
  /**通过给变成固定定位的元素添加一个同等高度的父元素，防止该元素变成固定定位时，脱离文档流导致的页面抖动 */
  this.tabsHeight = this.$refs.elTabs.offsetHeight;
  window.addEventListener("scroll", this.handleScroll);
 },
 destroyed() {
  //离开该页面需要移除这个监听的事件
  window.removeEventListener("scroll", this.handleScroll);
 },
  methods: {
  /**滚动事件 */
  handleScroll() {
    //获取页面滚动条的高度
    let scrollTop = window.pageYOffset || document.documentElement.scrollTop || document.body.scrollTop;
    let offsetTop = this.getOffsetTop(this.$refs.elTabs);
    this.isFixed = scrollTop > offsetTop;
  }
 }

/**滚动事件 */
  handleScroll() {
   /**
    * getBoundingClientRect().top 获取某元素距离浏览器顶部的高度，不包含滚动的距离
    this.offsetTop 表示的是吸顶元素距离顶部的条件值（一般项目需求是0）
    */
   let tabOffsetTop = this.$refs.stickyBox.getBoundingClientRect().top;
   this.isFixed = tabOffsetTop < this.offsetTop
  }

<a href="#view1">按钮1</a> 
 <a href="#view2">按钮1</a> 
 <div id="view1">视图1</div> 
 <div><a name="view2">视图2</a></div> 

<!-- html -->
 <el-tabs v-model="activeName" type="card" @tab-click="tabClick">
  <el-tab-pane :label="item.name" :name="item.key" v-for="item in tabList" :key="item.key"></el-tab-pane>
</el-tabs>
<!-- js -->
methods:{
 //获取当前元素的offsetTop
 getOffsetTop(obj) {
  let offsetTop = 0;
  while (obj != window.document.body && obj != null) {
  offsetTop += obj.offsetTop;
  obj = obj.offsetParent;
 }
  return offsetTop;
 },
 <!--锚点点击事件-->
 <!--fixedHeight 滚动的位置上方固定的高度-->
 tabClick(e) {
  let _this = this;
  //获取当前选中的index以便后面滚动高亮
  this.index = parseInt(e.index);
  //给定一个标识，锚点事件不触发滚动
  this.isScroll = false;
  this.isChange = false;
  //获取当前选中元素的top值（给元素绑定对应的ref值）
  let offsetTop = this.getOffsetTop(this.$refs[this.activeName]);
  let scrollTop = offsetTop - this.fixedHeight;
  window.scrollTo({
    top: scrollTop
  });
}

//页面滚动要做的事情
handleScroll() {
  let scrollTop =
    window.pageYOffset ||
    document.documentElement.scrollTop ||
    document.body.scrollTop;
   this.scrollTop = scrollTop;
   <!--isScroll 用于避免锚点事件触发页面滚动-->
   if (!this.isScroll) return;
   /**
    * scrollTop 页面的滚动条的高度
    * offsetTop 当前选中的tab元素的offsetTop
    * offsetHeight 当前选中元素的高度
    */
   let offsetTop = this.getOffsetTop(this.$refs[this.activeName]);
   let offsetHeight = this.$refs[this.activeName].offsetHeight;
   let actuaTop = scrollTop + this.fixedHeight;
   let length = this.tabList.length;
   /**
    * 页面滚动中根据相应位置变换选中tab
    */
   if (actuaTop < offsetTop && this.index > 0) {
    this.index = this.index - 1;
    this.activeName = this.tabList[this.index].key;
   } else if (this.index < length && actuaTop > offsetTop + offsetHeight) {
    this.index = this.index + 1;
    this.activeName = this.tabList[this.index].key;
 }
}