1.安装依赖：

命令行：引入相应的axios和vue-axios

cnpm install axios vue-axios -S

2.axios封装

接下来我们使用class来封装，而不是传统的函数封装，因为类更具有可塑性，更加灵活。

2.1创建request.js

import axios, {AxiosInstance, AxiosRequestConfig, AxiosResponse} from 'axios';
import {message, notification} from 'ant-design-vue';
 
export class Request {
    public static axiosInstance: AxiosInstance;
 
    // constructor() {
    //     // 创建axios实例
    //     this.axiosInstance = axios.create({timeout: 1000 * 12});
    //     // 初始化拦截器
    //     this.initInterceptors();
    // }
 
    public static init() {
        // 创建axios实例
        this.axiosInstance = axios.create({
            baseURL: '/api',
            timeout: 6000
        });
        // 初始化拦截器
        this.initInterceptors();
        return axios;
    }
 
    // 为了让http.ts中获取初始化好的axios实例
    // public getInterceptors() {
    //     return this.axiosInstance;
    // }
 
 
 
    // 初始化拦截器
    public static initInterceptors() {
        // 设置post请求头
        this.axiosInstance.defaults.headers.post['Content-Type'] = 'application/x-www-form-urlencoded';
        /**
         * 请求拦截器
         * 每次请求前，如果存在token则在请求头中携带token
         */
        this.axiosInstance.interceptors.request.use(
            (config: AxiosRequestConfig) => {
 
                // const token = Vue.ls.get(ACCESS_TOKEN)
                // if (token) {
                //     config.headers['Authorization'] = 'Bearer ' + token
                // }
 
                // 登录流程控制中，根据本地是否存在token判断用户的登录情况
                // 但是即使token存在，也有可能token是过期的，所以在每次的请求头中携带token
                // 后台根据携带的token判断用户的登录情况，并返回给我们对应的状态码
                // if (config.headers.isJwt) {
                    const token = localStorage.getItem('ACCESS_TOKEN');
                    if (token) {
                        config.headers.Authorization = 'Bearer ' + token;
                    }
                // }
                return config;
            },
            (error: any) => {
                console.log(error);
            },
        );
 
 
        // 响应拦截器
        this.axiosInstance.interceptors.response.use(
            // 请求成功
            (response: AxiosResponse) => {
                // if (res.headers.authorization) {
                //     localStorage.setItem('id_token', res.headers.authorization);
                // } else {
                //     if (res.data && res.data.token) {
                //         localStorage.setItem('id_token', res.data.token);
                //     }
                // }
 
                if (response.status === 200) {
                    // return Promise.resolve(response.data);
                    return response;
                } else {
                    Request.errorHandle(response);
                    // return Promise.reject(response.data);
                    return response;
                }
            },
            // 请求失败
            (error: any) => {
                const {response} = error;
                if (response) {
                    // 请求已发出，但是不在2xx的范围
                    Request.errorHandle(response);
                    return Promise.reject(response.data);
                } else {
                    // 处理断网的情况
                    // eg:请求超时或断网时，更新state的network状态
                    // network状态在app.vue中控制着一个全局的断网提示组件的显示隐藏
                    // 关于断网组件中的刷新重新获取数据，会在断网组件中说明
                     ElMessage({
				        message: '网络连接异常,请稍后再试!',
				        type: 'success',
				      })
                }
            });
    }
 
 
    /**
     * http握手错误
     * @param res 响应回调,根据不同响应进行不同操作
     */
    private static errorHandle(res: any) {
        // 状态码判断
        switch (res.status) {
            case 401:
                break;
            case 403:
                break;
            case 404:
                ElMessage({
				        message: '请求的资源不存在',
				        type: 'warning',
				      })
                break;
            default:
                ElMessage.error('连接错误');
        }
    }
 
 
}

2.2 main.ts中引入axios和request

import { createApp } from 'vue'
import App from './App.vue'
import { Request } from '@/service/request'
import VueAxios from 'vue-axios'

import ElementPlus from 'element-plus'
import 'element-plus/dist/index.css'

import router from './router'
import store from './store'
import { components } from './plugins/element-plus'

const app = createApp(App)
for (const cpn of components) {
  app.component(cpn.name, cpn)
}
app.use(store)
app.use(router)
app.use(ElementPlus)
app.use(VueAxios, Request.init())
app.mount('#app')

2.3 编写接口 api.js

import { Request } from './request'

export function login (parameter: any)  {
    return Request.axiosInstance({
        url: '/cxLogin',
        method: 'post',
        data: parameter
    })
}
export function getUserList(parameter?: any) {
  return Request.axiosInstance({
    url: '/users',
    method: 'get',
    data: parameter
  })
}

export function home(parameter?: any) {
  return Request.axiosInstance({
    url: '/home',
    method: 'post',
    data: parameter
  })
}

3. vue组件中使用

<template>
  <div class="login-container">
   
        <el-form  :model="loginForm" @submit="handleSubmit"><!--@submit.native.prevent-->
          <el-form-item>
            <el-input v-model="loginForm.account" placeholder="account" style="width: 350px" >
           </el-input>
          </el-form-item> 
           <el-form-item> 
            <el-input v-model="loginForm.password" type="password" placeholder="Password" style="width: 350px">
             
            </el-input>
          </el-form-item>
          <el-form-item>
            <el-button type="primary" @click="handleSubmit">
              登陆
            </el-button>
          </el-form-item>
        </el-form>
     
  </div>
</template>
 
<script lang="ts">
import '../../reset.scss'
import '../../global.css'
import { defineComponent, reactive } from "vue";
import { login } from '@/service/api'
 
import { useRouter } from 'vue-router'
 
export default defineComponent({
  name: "index",
  components: {
  
  },
  setup(){
    const loginForm = reactive({
      account: '',
      password:''
    })
    const router = useRouter()
 
    const handleSubmit  = (e: Event)=> {
      const param =  {
        account: loginForm.account,
        password: loginForm.password
      }
      login(param).then(response => {
        const res: any = response.data
        if(res.code === 200){
          localStorage.setItem('ACCESS_TOKEN', res.data);
          router.push("/flow")
        }
      })
    }
    return{
      loginForm,
      handleSubmit
    }
  }
})
</script>
 
<style lang="scss" scoped>

</style>