webpack4 多页面打包

方式一:
	将entry修改为对象形式的多入口方式,每个入口对应对应一个html-webpack-plugin
	通过html-webpack-plugin中的chunks属性,引入entry中对应的chunk

方式二:
	在方法中通过glob或fs来匹配指定文件夹下的文件,遍历生成webpack对应的entry和html-webpack-plugin配置

	方式一:
		通过glob匹配目录后通过正则得到文件夹名称
	
	方式二:
		通过fs模块来获取文件信息
		const files = fs.readdirSync('./src')   获取路径下的所有文件名
		  files.forEach(function (item, index) {
		    let stat = fs.lstatSync("./src/" + item)  获取路径中的文件信息
		    if (stat.isDirectory() === true) { 
		      是文件夹的情况
		  }
		})
		
		通过path.dirname解析绝对路径获取到的文件夹名称会包含绝对路径的信息,所以使用fs

代码示例:

const path = require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const { CleanWebpackPlugin } = require('clean-webpack-plugin');
const HTMLInlineCSSWebpackPlugin = require ( "html-inline-css-webpack-plugin" ). default ;
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const glob = require('glob');
const fs = require('fs');

//多页面配置entry和htmlWebpackPlugin
const setOptions = ()=>{
  const entry = {};
  const htmlWebpackPlugin = [];

  const entryFiles = glob.sync(path.resolve(__dirname, './src/*/index.js'))
  const fileReg = /src\/(.*)\/index\.js/;

  entryFiles.forEach((filePath, index) => {
    const fileName = filePath.match(fileReg);
    
    entry[fileName[1]] = filePath;
    htmlWebpackPlugin.push(
      new HtmlWebpackPlugin({
        template: `./src/${fileName[1]}/index.html`,
        filename:fileName[1]+'.html',
        chunks:[fileName[1]]
      })
    )
  })


  return {
    entry,
    htmlWebpackPlugin
  }
}

module.exports = {
  // entry: './src/index.js',
  entry: setOptions().entry,
  output: {
    path: path.resolve(__dirname, 'dist'),
    filename:'[name]_[chunkhash:8].js'
  },
  module: {
    rules: [
      {
        test: /\.js$/,
        use:['babel-loader']
      },
      {
        test: /\.css$/,
        use: [
          MiniCssExtractPlugin.loader,
          'css-loader',
          {
            loader: "postcss-loader",
            options: {
              postcssOptions: {
                plugins: [
                  [
                    "autoprefixer",
                    {
                      overrideBrowserslist: [
                          "Android 4.1",
                          "iOS 7.1",
                          "Chrome > 31",
                          "ff > 31",
                          "ie >= 8",
                          "> 1%", // 必须大于 1% 用户使用的浏览器
                          //'last 2 versions', // 所有主流浏览器最近的 2个版本
                      ],
                    },
                  ],
                ],
              },
            },
          },
          {
            loader: 'px2rem-loader',
            options: {
              remUnit: 75, //初始稿的10分之一,代表设计稿为750,1rem=75px,
              remPrecision:8,  //精确的小数点位数
            }
          }
        ]
      },
      {
        test: /\.txt$/i,
        use: [
          {
            loader: 'raw-loader',
            options: {
              esModule: false,
            },
          },
        ],
      }
    ]
  },
  mode: "development",
  plugins: [
    ...setOptions().htmlWebpackPlugin,
    new MiniCssExtractPlugin({filename:'css/build.css'}),
    new HTMLInlineCSSWebpackPlugin(),
    new CleanWebpackPlugin()
  ]
}