webpack.config.js

var path = require('path');

const ExtractTextPlugin = require("extract-text-webpack-plugin");

const extractSass = new ExtractTextPlugin({
    filename: "style.css",
    // disable: process.env.NODE_ENV === "development"
});

module.exports = {
    context: path.resolve(__dirname, 'src'),
    entry: './index.js',
    output: {
        filename: 'bundle.js',
        path: path.resolve(__dirname, 'dist')
    },
    module: {
        loaders: [
            {
                test: /\.scss$/,
                use: extractSass.extract({
                    use: [{
                        loader: "css-loader"
                    }, {
                        loader: "sass-loader"
                    }],
                    // use style-loader in development
                    fallback: "style-loader"
                })
            },
            {
                test: /\.jsx?$/, // 匹配'js' or 'jsx' 后缀的文件类型
                exclude: /(node_modules|bower_components)/, // 排除某些文件
                loader: 'babel-loader', // 使用'babel-loader'也是一样的
                query: { // 参数
                    presets: ['es2015']
                }
            }
        ]
    },
    plugins: [
        extractSass
    ]
};

// webpack.config.js
var ExtractTextPlugin = require("extract-text-webpack-plugin");
module.exports = {
    // The standard entry point and output config
    entry: {
        posts: "./posts",
        post: "./post",
        about: "./about"
    },
    output: {
        filename: "[name].js",
        chunkFilename: "[id].js"
    },
    module: {
        loaders: [
            // Extract css files
            {
                test: /\.css$/,
                loader: ExtractTextPlugin.extract("style-loader", "css-loader")
            },
            // Optionally extract less files
            // or any other compile-to-css language
            {
                test: /\.less$/,
                loader: ExtractTextPlugin.extract("style-loader", "css-loader!less-loader")
            }
            // You could also use other loaders the same way. I. e. the autoprefixer-loader
        ]
    },
    // Use the plugin to specify the resulting filename (and add needed behavior to the compiler)
    plugins: [
        new ExtractTextPlugin("[name].css")
    ]
}

package.json

{
  "scripts": {
    "watch": "webpack -d --watch",
    "build": "webpack -p"
  },
  "devDependencies": {
    "babel-core": "^6.25.0",
    "babel-loader": "^7.1.1",
    "babel-preset-env": "^1.6.0",
    "babel-preset-es2015": "^6.24.1",
    "css-loader": "^0.28.4",
    "extract-text-webpack-plugin": "^3.0.0",
    "node-sass": "^4.5.3",
    "sass-loader": "^6.0.6",
    "style-loader": "^0.18.2",
    "webpack": "^3.3.0"
  }
}