axios 是一个基于Promise 用于浏览器和 nodejs 的 HTTP 客户端
npm install axios进行安装
之后我创建了http.js来引用

import axios from 'axios'
const service = axios.create({
    baseURL: "http://localhost", // url = base url + request url
    withCredentials: false, // send cookies when cross-domain requests 跨域要设置成false
    timeout: 5000 // request timeout
})

• 设置请求拦截器

service.interceptors.request.use(
    config => {
        // 不传递默认开启loading
        if (config.method === 'post' || config.method === 'put') {
            // post、put 提交时，将对象转换为string, 为处理Java后台解析问题
           // config.data = JSON.stringify(config.data)
        }
        config.headers.authentication = 'token:'+getToken()
        return config
    },
    error => {
        // do something with request error
        console.log(error) // 打印错误
        return Promise.reject(error)
    }
)

• 设置响应拦截器

service.interceptors.response.use(
    response => {
        const res = response.data
        if (res.status && res.status !== 200) {
              //拦截错误
            return Promise.reject(res || 'error')
        } else {
            setToken(res.headers.authentication)
            return Promise.resolve(res)
        }
    },
    error => {
        return Promise.reject(error)
    }
)

• 对常用的请求方式进行封装

export function get(url, params, headers) {
    const options = {}

    if (params) {
        options.params = params
    }
    if (headers) {
        options.headers = headers
    }
    return service.get(url, options)
}
export function post(url, data, params, headers) {
    const options = {}

    if (params) {
        options.params = params
    }
    if (headers) {
        options.headers = headers
    }
    return service.post(url, data, options)
}
export function put(url, params, headers) {
    const options = {}

    if (headers) {
        options.headers = headers
    }
    return service.put(url, params, options)
}
export function del(url, params, headers){
    const options = {}

    if (params) {
        options.params = params
    }
    if (headers) {
        options.headers = headers
    }
    return service.delete(url, options)
}
export default service

• token的一些操作

const TokenKey = 'LocalToken';
export function getToken() {//获取TokenKey值
    return window.localStorage.getItem(TokenKey)
}
export function setToken(tokenData) {//设置TokenKey值
    return localStorage.setItem(TokenKey, JSON.stringify(tokenData))
}

export function removeToken() {//
    return window.localStorage.removeItem(TokenKey)
}