问题1：Vue3如何全局使用axios？（3步骤）

1.安装axios

npm install axios -S

2.引入axios

// main.js
import { createApp } from 'vue'
import App from './App.vue'
import router from './router'
import axios from 'axios'
const app = createApp(App)
app.config.globalProperties.$axios = axios
app.use(store).use(router).mount('#app')

3.使用axios

// xxx.vue
import { defineComponent, getCurrentInstance, onMounted } from "vue";
export default defineComponent({
	setup(props, ctx) {
		const { proxy } = getCurrentInstance()
		onMounted(() => {
			getData()
		})
		getData() {
			proxy.$axios.get('xxxxx').then(res => {})
		}
	}
})