1.安装插件：npm install optimize-css-assets-webpack-plugin -D
2.在webpack.config.js中引入使用该插件：
const{resolve}=require('path');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const MiniCssExtractPlugin = require('mini-css-extract-plugin');
const OptimizeCssAssetsWebpackPlugin = require('optimize-css-assets-webpack-plugin');
const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin');//引入插件
module.exports={
entry:{
vender:['./src/js/jquery.js','./src/js/common.js'],
index:'./src/js/index.js',
cart:'./src/js/cart.js'
},
output:{
path:resolve(__dirname,'build'),
filename:'[name].js'
},
mode:'development',
module:{
rules:[
//{test:/.css$/,use:['style-loader','css-loader']},
{test:/.css$/,use:[MiniCssExtractPlugin.loader,'css-loader','postcss-loader']},
{test:/.less$/,use:[MiniCssExtractPlugin.loader,'css-loader','less-loader','postcss-loader']},
{test:/.scss$/,use:[MiniCssExtractPlugin.loader,'css-loader','sass-loader','postcss-loader']}
]
},
plugins:[
new HtmlWebpackPlugin({
template:'./src/index.html',
filename:'index.html',
chunks:['vender','index']
}),
new HtmlWebpackPlugin({
template:'./src/cart.html',
filename:'cart.html',
chunks:['vender','cart']
}),
new MiniCssExtractPlugin({
filename:'index.css'
}),
new OptimizeCssAssetsPlugin()//使用插件，这里直接new一个对象使用默认配置，默认配置会去掉空格注释之类的。如果要自己手动配置压缩项也可以在这里配置。
]
}