vue-cli4 添加axios后报错：Cannot read property ‘use‘ of undefined

执行vue add axios 后需要添加全局属性，在main.js里添加

import { createApp } from 'vue'
import App from './App.vue'
import router from './router'
import store from './store'
import axios from "axios";

const app = createApp(App);
app.config.globalProperties.axios = axios;  // 添加全局属性
app.use(store).use(router).mount('#app');

使用：

this.axios.get("http://localhost:8181/book/books").then(function(res){})```