React应用程序将JS转换为ES5以实现目标IE 11

Question

我目前有一个react应用程序，它不能在IE中运行/渲染，我想是因为ES5 / ES6的问题。

我得到的错误是:语法错误。

在下面突出显示的行上。

    if(process.env.NODE_ENV == 'production') {
=>       module.exports = require('./cjs/react.production.min.js');
    } else {
      module.exports = require('./cjs/react.development.js');

在编译前的index.js顶部：

import 'babel-polyfill'; 
import 'react-app-polyfill/ie11';
import 'react-app-polyfill/stable';

package.json：

{
  "name": "reactapp",
  "version": "0.1.0",
  "private": true,
  "dependencies": {
    "@babel/polyfill": "^7.8.3",
    "@material-ui/core": "^3.9.3",
    "@material-ui/icons": "^3.0.2",
    "@sentry/browser": "^5.10.2",
    "adblockdetect": "0.0.2",
    "animatewithsass": "^3.2.1",
    "axios": "^0.18.1",
    "babel-polyfill": "^6.26.0",
    "core-js": "^3.6.5",
    "date-fns": "^2.10.0",
    "detectrtc": "^1.4.0",
    "easy-peasy": "^3.2.0",
    "formik": "^2.0.3",
    "google-map-react": "^1.1.5",
    "js-cookie": "^2.2.1",
    "lodash": "^4.17.15",
    "material-design-icons": "^3.0.1",
    "material-icons": "^0.3.1",
    "node-sass": "^4.13.0",
    "platform": "^1.3.5",
    "query-string": "^6.10.1",
    "react": "^16.11.0",
    "react-albus": "^2.0.0",
    "react-app-polyfill": "^1.0.6",
    "react-color": "^2.18.0",
    "react-confirm-alert": "^2.4.1",
    "react-dom": "^16.11.0",
    "react-dropzone": "^11.1.0",
    "react-loader-spinner": "^3.1.5",
    "react-media-recorder": "^1.2.0",
    "react-paginate": "^6.3.2",
    "react-router-dom": "^5.1.2",
    "react-rtc-real": "^1.11.22",
    "react-scripts": "2.1.8",
    "react-select": "^3.1.0",
    "react-simple-line-icons": "^1.0.8",
    "react-spring": "^8.0.27",
    "react-stripe-elements": "^5.1.0",
    "react-stripe-script-loader": "^1.0.16",
    "react-switch": "^5.0.1",
    "react-toastify": "^5.4.0",
    "react-toggle": "^4.1.1",
    "react-tooltip": "^3.11.2",
    "regenerator-runtime": "^0.13.5",
    "semantic-ui-css": "^2.4.1",
    "semantic-ui-react": "^0.88.2",
    "styled-components": "^4.4.1",
    "sweetalert2-react": "^0.8.3",
    "videojs": "^1.0.0",
    "videojs-record": "^4.0.0",
    "webfontloader": "^1.6.28",
    "webrtc-adapter": "^7.5.1",
    "yup": "^0.27.0"
  },
  "scripts": {
    "start": "react-app-rewired start",
    "build": "set NODE_ENV=production && react-app-rewired build",
    "test": "react-app-rewired test",
    "eject": "react-scripts eject"
  },
  "eslintConfig": {
    "extends": "react-app"
  },
  "browserslist": {
    "production": [
      ">0.2%",
      "not dead",
      "not op_mini all",
      "IE 11"
    ],
    "development": [
      "last 1 chrome version",
      "last 1 firefox version",
      "last 1 safari version",
      "IE 11"
    ]
  },
  "devDependencies": {
    "animate-sass": "^0.8.2",
    "es-check": "^5.1.1",
    "react-app-rewired": "^2.1.6"
  }
}

.babelrc内幕

{
    "presets": ["@babel/env","@babel/preset-react",["@babel/preset-env", { "targets": "defaults" }]],
    "plugins" : ["@babel/plugin-syntax-dynamic-import"]
}

有没有人可以指导我如何让babel为ES5编译正确的东西呢？你会注意到，我使用的是react-app-rewired，而不是弹出，我认为这不会造成问题，所以感谢任何帮助。

更新：

"Object doesn't support property or method 'repeat'" - when running in development mode. How do I polyfill this? I think this may be the problem.  

Answer 1

这与this Github issue in core-js非常相似

正如该帖子中所建议的，您可以将其添加到您的预设配置中

 { modules: false,
   useBuiltIns: 'entry',
   corejs: 3 }

或者直接导入函数

import 'core-js/features/string/repeat';

Answer 2

在index.js文件中，第一个导入是导入“babel-polyfill”；我认为应该是@babel/polyfill。但这并不能解决IE 11的问题。

我们遇到了类似的问题，不得不切换到core-js来进行捆绑--你已经有了。但是你需要@babel/core和@babel/ But corejs3作为开发依赖项。

您的预设需要更改

presets: [
             [
                 "@babel/preset-env", {
                 "useBuiltIns": "usage", 
                 corejs: { version: 3, proposals: true }
                 }
              ]
           ]

然后替换index.js中的代码

 imports babel/polyfill;

使用

import 'core-js/stable';

Answer 3

如果您可以使用typescript，那么我建议您可以转换您的tsconfig.js文件并将target更改为es5。

如果没有，则创建.babelrc文件，并在其中添加以下内容：

{ "presets": [ [ "@babel/preset-env", { "useBuiltIns": "entry", "forceAllTransforms": true, "corejs": "3.0.0", "targets": { "ie": "11" } } ] D18 }