1、html代码:

定义了isBottom来判断是否到底部,点击调用toBottom(100)去底部的函数
<div
        v-show="!isBottom"
        style="position:fixed;width:40px;height:40px;display:inline-block;bottom:58px;right:100px;"
      >
        <div
          @click="toBottom(100)"
          style=" {
        display:inline-block;
        height: 100%;
        width:100%;
        background-color: #f2f5f6;
        box-shadow: 0 0 6px rgba(0,0,0, .12);
        text-align: center;
        line-height: 20px;
        color: #1989fa;
        font-size:16px;
      }"
        >回到底部</div>
      </div>

2、vue的js部分代码:<script>

import{ DATE_FORMAT, ALL}from "@/components";

export default {
  data() {
    return {
 
     ALL,
        DATE_FORMAT,

      isBottom: false
        }
    },
   computed:{},
    created(){},
    methods:{
    toBottom(i) {
      let clientHeight =
        document.documentElement.clientHeight || document.body.clientHeight;
      let scrollHeight = document.documentElement.scrollHeight;
      let rollheight = scrollHeight - clientHeight; //超出窗口上界的值就是底部的scrolTop的值
      document.documentElement.scrollTop += 200;
      if (document.documentElement.scrollTop + 1 <= rollheight) {//之所以+1,可以打印这两个值的日志就知道了,下面+1也是同理
        var c = setTimeout(() => this.toBottom(i), 10);//调用setTimeout是为了“回到底部”这过程不是一瞬间
      } else {
        clearTimeout(c);
      }
    },
    scrollHandle(e) {
      let clientHeight =
        document.documentElement.clientHeight || document.body.clientHeight;
      let scrollHeight = document.documentElement.scrollHeight;
      let rollheight = scrollHeight - clientHeight;
      let top = e.srcElement.scrollingElement.scrollTop; // 获取页面滚动高度
      if (rollheight <= top + 1) {
        this.isBottom = true;
      } else {
        this.isBottom = false;
      }
    }
    },
    mounted(){
     window.addEventListener("scroll", this.scrollHandle); //绑定页面滚动事件
    }
};
</script>