// src/utils/history.js

const History = {
 _history: [], // 历史记录堆栈
 install(Vue) {
  // 提供Vue插件所需安装方法
  Object.defineProperty(Vue.prototype, '$routerHistory', {
   get() {
    return History;
   }
  })
 },
 push(path) { // 入栈
  this._history.push(path);
 },
 pop() {
  this._history.pop();
 },
 canBack(){
  return this._history.length > 1;
 }

}
export default History;

// src/router.js

import Vue from 'vue'
import Router from 'vue-router'
import History from './utils/history';

Vue.use(Router);
Vue.use(History);

// 实例化之前，扩展Router
Router.prototype.goBack = function () {
 this.isBack = true;
 this.back();
}

// src/router.js

// afterEach记录历史记录
router.afterEach((to, from) => {
 if (router.isBack) {
 // 后退
 History.pop();
 router.isBack = false;
 router.transitionName = 'route-back';
 } else {
 History.push(to.path);
 router.transitionName = 'route-forward';
 }
})

// Hearder.vue

<template>
 <div class="header">
 <h1>{{title}}</h1>
 <i v-if="$routerHistory.canBack()" @click="back"></i>
 <div class="extend">
  <slot></slot>
 </div>
 </div>
</template>

<script>
export default {
 props: {
 title: {
  type: String,
  default: ""
 }
 },
 methods: {
 back() {
  this.$router.goBack();
 }
 }
};
</script>