使用antd按需加载

使用antd按需加载
使用react-app-rewired对 create-react-app 的默认配置进行自定义

yarn add react-app-rewired --dev

/* package.json */
"scripts": {
-   "start": "react-scripts start",
+   "start": "react-app-rewired start",
-   "build": "react-scripts build",
+   "build": "react-app-rewired build",
-   "test": "react-scripts test --env=jsdom",
+   "test": "react-app-rewired test --env=jsdom",
}

2.然后在项目根目录创建一个 config-overrides.js 用于修改默认配置。
module.exports = function override(config, env) {
  // do stuff with the webpack config...
  return config;
};

使用 babel-plugin-import
babel-plugin-import 是一个用于按需加载组件代码和样式babel 插件（原理），现在我们尝试安装它并修改config-overrides.js 文件
1.yarn add babel-plugin-import --dev
+ const { injectBabelPlugin } = require('react-app-rewired');

  module.exports = function override(config, env) {
+   config = injectBabelPlugin(['import', { libraryName: 'antd', libraryDirectory: 'es', style: 'css' }], config);
    return config;
  };

或者也可修改
{
            test: /\.(js|jsx|mjs)$/,
            include: paths.appSrc,
            loader: require.resolve('babel-loader'),
            options: {
              plugins: [
                ['import', { libraryName: 'antd', style: true }],
              ],
              // This is a feature of `babel-loader` for webpack (not Babel itself).
              // It enables caching results in ./node_modules/.cache/babel-loader/
              // directory for faster rebuilds.
              cacheDirectory: true,
            },
          },

自定义主题

yarn add react-app-rewire-less --dev

  const { injectBabelPlugin } = require('react-app-rewired');
+ const rewireLess = require('react-app-rewire-less');

  module.exports = function override(config, env) {
-   config = injectBabelPlugin(['import', { libraryName: 'antd', style: 'css' }], config);
+   config = injectBabelPlugin(['import', { libraryName: 'antd', style: true }], config);
+   config = rewireLess.withLoaderOptions({
+     modifyVars: { "@primary-color": "#1DA57A" },
+   })(config, env);
    return config;
  };

参考链接：https://ant.design/docs/react/use-with-create-react-app-cn
使用less
如果已经配置react-app-rewire-less，则无需再进行此操作
1.npm install less-loader less --save-dev
2.修改node_modules/react_script/config下的webpack.config.dev.js 和 webpack.config-prod.js 配置文件

test: /.css$/ 改为 /.(css|less)$/
test: /.css$/ 的 use 数组配置增加 less-loader

{
  test: /\.(css|less)$/,
  use: [
    require.resolve('style-loader'),
    {
      loader: require.resolve('css-loader'),
      options: {
        importLoaders: 1,
      },
    },
    {
      loader: require.resolve('postcss-loader'),
      options: {
        // Necessary for external CSS imports to work
        // https://github.com/facebookincubator/create-react-app/issues/2677
        ident: 'postcss',
        plugins: () => [
          require('postcss-flexbugs-fixes'),
          autoprefixer({
            browsers: [
              '>1%',
              'last 4 versions',
              'Firefox ESR',
              'not ie < 9', // React doesn't support IE8 anyway
            ],
            flexbox: 'no-2009',
          }),
        ],
      },
    },
    {
      loader: require.resolve('less-loader') // compiles Less to CSS
    }
  ],
},

使用css Module
antd 和 css modules 不能混用,针对antd的css 单独写一条loader的规则,不开启 css modules。

使用 exclude 和 include 配置(https://segmentfault.com/q/1010000011223900),修改webpack.config.dev.js 和 webpack.config-prod.js 配置文件 (尽量不要使用less-loader 来处理css文件，在与antd一起使用时可能出现错误，单独写一条规则)

        {
            test: /\.css$/,
            exclude: /node_modules|antd\.css/,
            use: [
              require.resolve('style-loader'),
              {
                loader: require.resolve('css-loader'),
                options: {
                  importLoaders: 1,
                  modules: true,   // 新增对css modules的支持
                  localIdentName: '[name]__[local]__[hash:base64:5]',
                },
              },
              {
                loader: require.resolve('postcss-loader'),
                options: {
                  // Necessary for external CSS imports to work
                  // https://github.com/facebookincubator/create-react-app/issues/2677
                  ident: 'postcss',
                  plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    autoprefixer({
                      browsers: [
                        '>1%',
                        'last 4 versions',
                        'Firefox ESR',
                        'not ie < 9', // React doesn't support IE8 anyway
                      ],
                      flexbox: 'no-2009',
                    }),
                  ],
                },
              },
            ],
          },
          {
            test: /\.less$/,
            exclude: /node_modules|antd\.less/,
            use: [
              require.resolve('style-loader'),
              {
                loader: require.resolve('css-loader'),
                options: {
                  importLoaders: 1,
                  modules: true,   // 新增对css modules的支持
                  localIdentName: '[name]__[local]__[hash:base64:5]',
                },
              },
              {
                loader: require.resolve('postcss-loader'),
                options: {
                  // Necessary for external CSS imports to work
                  // https://github.com/facebookincubator/create-react-app/issues/2677
                  ident: 'postcss',
                  plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    autoprefixer({
                      browsers: [
                        '>1%',
                        'last 4 versions',
                        'Firefox ESR',
                        'not ie < 9', // React doesn't support IE8 anyway
                      ],
                      flexbox: 'no-2009',
                    }),
                  ],
                },
              },
              {
                loader: require.resolve('less-loader') // compiles Less to CSS
              },
            ],
          },
          {
            test: /\.(css)$/,
            include: /node_modules|antd\.css/,
            use: [
              require.resolve('style-loader'),
              {
                loader: require.resolve('css-loader'),
                options: {
                  importLoaders: 1,
                },
              },
              {
                loader: require.resolve('postcss-loader'),
                options: {
                  // Necessary for external CSS imports to work
                  // https://github.com/facebookincubator/create-react-app/issues/2677
                  ident: 'postcss',
                  plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    autoprefixer({
                      browsers: [
                        '>1%',
                        'last 4 versions',
                        'Firefox ESR',
                        'not ie < 9', // React doesn't support IE8 anyway
                      ],
                      flexbox: 'no-2009',
                    }),
                  ],
                },
              },
            ],
          },
          {
            test: /\.(less)$/,
            include: /node_modules|antd\.less/,
            use: [
              require.resolve('style-loader'),
              {
                loader: require.resolve('css-loader'),
                options: {
                  importLoaders: 1,
                },
              },
              {
                loader: require.resolve('postcss-loader'),
                options: {
                  // Necessary for external CSS imports to work
                  // https://github.com/facebookincubator/create-react-app/issues/2677
                  ident: 'postcss',
                  plugins: () => [
                    require('postcss-flexbugs-fixes'),
                    autoprefixer({
                      browsers: [
                        '>1%',
                        'last 4 versions',
                        'Firefox ESR',
                        'not ie < 9', // React doesn't support IE8 anyway
                      ],
                      flexbox: 'no-2009',
                    }),
                  ],
                },
              },
              {
                loader: require.resolve('less-loader') // compiles Less to CSS
              },
            ],
          },