1. 在.eslintrc.js 添加 vscode 终端启动服务

   // 添加⾃定义规则
    'prettier/prettier': [
      // eslint校验不成功后，error或2则报错，warn或1则警告，off或0则⽆提示
      'error',
      {
        singleQuote: true,
        semi: false, //结束是否加分号
        printWidth: 160//每行最长字符 
      }
    ]

2.打开VS code 文件》首选项》设置》扩展》ESLint》

// eslint格式化字符串
    "editor.codeActionsOnSave": {
        "source.fixAll.eslint": true
    },

如果编译 发现以下错误
warning delete ·· (prettier/prettier)
“error Delete ⏎ prettier/prettier” in .vue files

解决
在vuejs项目中，运行如下命令解决：
npm run lint – --fix

如果还是没行，就要在 vue.config.js
添加
// vue.config.js

// 旧
data: @import "~@/assets/scss/variables.scss";
// 新
prependData: @import "~@/assets/scss/variables.scss";

module.exports = {
  chainWebpack: config => {
    config.module
      .rule('eslint')
      .use('eslint-loader')
      .loader('eslint-loader')
      .tap(options => {
        options.fix = true
        return options
      })
  }
}

 ERROR  Failed to compile with 1 errors                                                                                                                                   1:06:43
 error  in ./src/App.vue?vue&type=style&index=0&lang=scss&

Module build failed (from ./node_modules/sass-loader/dist/cjs.js):
ValidationError: Invalid options object. Sass Loader has been initialized using an options object that does not match the API schema.
 - options has an unknown property 'prependdata'. These properties are valid:
   object { implementation?, sassOptions?, prependData?, sourceMap?, webpackImporter? }
    at validate (E:\VUE\ElementUI\myProject\vue-manage\node_modules\schema-utils\dist\validate.js:85:11)
    at Object.loader (E:\VUE\ElementUI\myProject\vue-manage\node_modules\sass-loader\dist\index.js:36:28)

 @ ./node_modules/vue-style-loader??ref--8-oneOf-1-0!./node_modules/css-loader/dist/cjs.js??ref--8-oneOf-1-1!./node_modules/vue-loader/lib/loaders/stylePostLoader.js!./node_modules/postcss-loader/src??ref--8-oneOf-1-2!./node_modules/sass-loader/dist/cjs.js??ref--8-oneOf-1-3!./node_modules/cache-loader/dist/cjs.js??ref--0-0!./node_modules/vue-loader/lib??vue-loader-options!./src/App.vue?vue&type=style&index=0&lang=scss& 4:14-416 14:3-18:5 15:22-424
 @ ./src/App.vue?vue&type=style&index=0&lang=scss&
 @ ./src/App.vue
 @ ./src/main.js
 @ multi (webpack)-dev-server/client?http://192.168.3.30:3333/sockjs-node (webpack)/hot/dev-server.js ./src/main.js

css laoder没安装
安装
npm install sass-loader --save-dev
npm install node-sass --save-dev
npm install css-loader style-loader --save-dev