实现axios

  2. function axios({ method, url, params, data }) {
  3.     return new Promise((resolve, reject) => {
  5.         method = method.toUpperCase()
  7.         //1.创建对象
  8.         const xhr = new XMLHttpRequest();
  10.         //2.初始化
  11.         let str = '';
  12.         for (let k in params) {
  13.             str += `${k}=${params[k]}&`;
  14.         }
  15.         if (str) {
  16.             url = url + '?' + str.slice(0, -1);
  17.         }
  20.         xhr.open(method, url);
  22.         //3.发送
  23.         if (method === 'POST' || method === 'PUT' || method === 'DELETE') {
  24.             xhr.setRequestHeader('Content-type', 'application/json;charset=utf-8')
  25.             //设置请求体
  26.             xhr.send(JSON.stringify(data))
  27.         } else {
  28.             xhr.send();
  29.         }
  31.         //4.处理结果
  32.         xhr.onreadystatechange = function () {
  33.             if (xhr.readyState === 4) {
  34.                 if (xhr.status >= 200 && xhr.status < 300) {
  35.                     resolve({
  36.                         status: xhr.status,
  37.                         message: xhr.statusText,
  38.                         body: JSON.parse(xhr.response)
  39.                     })
  40.                 } else {
  41.                     reject(new Error('request error status is ' + xhr.status))
  42.                 }
  43.             }
  44.         }
  45.     })
  46. }
  49. axios.get = function (url, options) {
  50.     return axios(Object.assign(options, { url, method: 'get' }))
  51. }
  53. //post delete put 同
  55. // // 使用形式：
  56.  axios({
  58.      url: 'https://api.apiopen.top/getJoke',
  59.      method: 'GET',
  60.      params: {
  61.          a: 1,
  62.          b: 2
  63.      },
  64.      data: {
  65.          a: 2,
  66.          b: 4
  67.      }
  68.  }).then(
  69.      response => {
  70.          console.log(response)
  71.      }).catch(error => {
  72.          console.log(error)
  73.      })
  76. // 使用形式：
  77. axios.get('https://api.apiopen.top/getJoke', {
  78.     params: {
  79.         a: 1,
  80.         b: 2
  81.     }
  82. }).then(
  83.     response => {
  84.         console.log(response)
  85.     }).catch(error => {
  86.         console.log(error)
  87.     })

面试官：Vue项目中有封装过axios吗？怎么封装的？