react中配置less

首先安装less语言所需要的相关依赖

pm i less less-loader --save

然后打开项目中 config/webpack.config.js 一共修改了三处

//添加less配置
const lessRegex = /\.less$/;
const lessModuleRegex = /\.module\.less$/;

// 参数lessOptions为添加项
const getStyleLoaders = (cssOptions, lessOptions, preProcessor) => {
    const loaders = [
      isEnvDevelopment && require.resolve('style-loader'),
      isEnvProduction && {
        loader: MiniCssExtractPlugin.loader,
        options: shouldUseRelativeAssetPaths ? { publicPath: '../../' } : {},
      },
      {
        loader: require.resolve('css-loader'),
        options: cssOptions,
      },
      // 添加 Less 配置
      {
        loader: require.resolve('less-loader'), 
        options: lessOptions,
      },
      {
        // 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,
        },
      });
    }
    return loaders;
  };

  // 添加less配置
  {
    test: lessRegex,
    exclude: lessModuleRegex,
    use: getStyleLoaders(
    {
        importLoaders: 2,
        sourceMap: isEnvProduction && shouldUseSourceMap,
    },
    'less-loader'
    ),
    sideEffects: true,
},
{
    test: lessModuleRegex,
    use: getStyleLoaders(
    {
        importLoaders: 2,
        sourceMap: isEnvProduction && shouldUseSourceMap,
        modules: true,
        getLocalIdent: getCSSModuleLocalIdent,
    },
    'less-loader'
    ),
},

恭喜你，配置成功，重新运行项目，添加一个less文件，看看是否能正常运行，欢迎有问题大家一起讨论。