CRA版本为3.0.1。
eject出来之后只有一个webpack.config.js。不再区分为dev和prod两个配置文件。
首先安装 antd,less,less-loader
npm install antd
npm install less less-loader
eject CRA新建的项目
config目录下的文件如下：
image.png
修改webpack.config.js
首先配置less module
在cssRegex和sassRegex附近(line 42左右)添加如下代码
const lessRegex = /\.less$/;
const lessModuleRegex = /\.module\.less$/;
再找到使用cssRegex的代码位置(line 460左右）添加如下代码
{
test: lessRegex,
// exclude: lessModuleRegex,
exclude: /node_modules/,
use: getStyleLoaders(
{
modules: true,
importLoaders: 3,
// javascriptEnabled: true,
sourceMap: isEnvProduction
? shouldUseSourceMap
: isEnvDevelopment
},
"less-loader"
),
// Don't consider CSS imports dead code even if the
// containing package claims to have no side effects.
// Remove this when webpack adds a warning or an error for this.
// See https://github.com/webpack/webpack/issues/6571
sideEffects: true
},
{
test: lessRegex,
// exclude: lessModuleRegex,
include: /node_modules/,
use: getStyleLoaders(
{
importLoaders: 3,
// javascriptEnabled: true,
sourceMap: isEnvProduction
? shouldUseSourceMap
: isEnvDevelopment
},
"less-loader"
),
},
// Adds support for CSS Modules, but using SASS
// using the extension .module.scss or .module.sass
{
test: lessModuleRegex,
use: getStyleLoaders(
{
importLoaders: 3,
sourceMap: isEnvProduction
? shouldUseSourceMap
: isEnvDevelopment,
modules: true,
getLocalIdent: getCSSModuleLocalIdent
},
"less-loader"
)
},
注意上面的less-loader配置了2次，第一次主要是为了exclude antd。从而可以正确加载antd的样式。
修改getStyleLoaders方法
当前版本CRA生成的webpack.config.js文件加载css loader等都是通过getStyleLoaders方法（line74左右）实现的。但这个方法有点小问题，像上面那样配置了第二个参数“less-loader”,并没有被该方法使用。所以如下修改改方法
const getStyleLoaders = (cssOptions, preProcessor) => {
const loaders = [
isEnvDevelopment && require.resolve('style-loader'),
isEnvProduction && {
loader: MiniCssExtractPlugin.loader,
options: shouldUseRelativeAssetPaths ? { publicPath: '../../' } : {},
},
{
loader: require.resolve('css-loader'),
options: cssOptions,
},
{
// Options for PostCSS as we reference these options twice
// Adds vendor prefixing based on your specified browser support in
// package.json
loader: require.resolve('postcss-loader'),
options: {
// Necessary for external CSS imports to work
// https://github.com/facebook/create-react-app/issues/2677
ident: 'postcss',
plugins: () => [
require('postcss-flexbugs-fixes'),
require('postcss-preset-env')({
autoprefixer: {
flexbox: 'no-2009',
},
stage: 3,
}),
// Adds PostCSS Normalize as the reset css with default options,
// so that it honors browserslist config in package.json
// which in turn let's users customize the target behavior as per their needs.
postcssNormalize(),
],
sourceMap: isEnvProduction && shouldUseSourceMap,
},
},
].filter(Boolean);
if (preProcessor) {
loaders.push({
loader: require.resolve(preProcessor),
options: {
sourceMap: isEnvProduction && shouldUseSourceMap,
modifyVars: { '@primary-color': '#2577E0' },
javascriptEnabled: true,
},
});
}
return loaders;
};
增加了最后的if (preprocessor)的判断，触发less-loader及antd修改主题的相关配置。
到这里webpack的相关配置修改就完成了。
最后：
Antd的按需加载
npm install babel-plugin-import
先安装babel插件
然后在项目的根目录下（就是和package.json相同的层级）新建文件babel.config.js，里面的内容如下
module.exports = {
plugins: [
["import", { libraryName: "antd", style: true}] // `style: true` 会加载 less 文件
]
};
以上，Create-React-App新建项目，引入antd及按需加载，使用less作为业务代码的样式文件，并实现css模块化配置完成。
2019-8
