1.安装以下插件

• babel-plugin-transform-runtime
• babel-preset-stage-3

2.Webpack配置

module : {       loaders : [{           test: /\.jsx?$/,           exclude: /node_modules/,           loader: 'babel-loader',            query: {                "presets": ["react", "es2015", "stage-0"]                "plugins": [                    ["transform-runtime", {                        "polyfill": false,                        "regenerator": true                    }]                ]            },       }]    }

3.调用实例

let fetchApi = () => {       return new Promise((resolve, reject) => {           var xhr = new XMLHttpRequest();           xhr.onreadystatechange = function() {               if (xhr.readyState === 4) {                   if (xhr.status >= 200 && xhr.status < 300) {                       var response;                       try {                           response = JSON.parse(xhr.responseText);                       } catch (e) {                           reject(e);                       }                       if (response) {                           resolve(response, xhr.status, xhr);                       }                   } else {                       reject(xhr);                   }               }           };           xhr.open('GET', 'https://api.douban.com/v2/user/aisk', true);           xhr.setRequestHeader("Content-Type", "text/plain");           xhr.send(xhr);       })   }  let testAsync = async () => {      const t = await fetchApi()      console.log(t)   }   testAsync()