ES6语法转化
注意：开始之前以下内容之前，需要配置一些webpack的基础配置，传送门：学习webpack4.x – 基础配置
当前目录结构为
clipboard.png
index.js 文件内容：
require(‘./index.css’);
require(‘./index.scss’);
webpack.config.js文件内容：
let path = require(‘path’);
let HtmlWebpackPlugin = require(‘html-webpack-plugin’);
let MiniCssExtractPlugin = require(‘mini-css-extract-plugin’); //抽离CSS
let OptimizeCssPlugin = require(‘optimize-css-assets-webpack-plugin’); //优化项，比如压缩css等
let UglifyJsPlugin = require(‘uglifyjs-webpack-plugin’); //压缩js
module.exports = {
// mode: ‘development’,
//优化项配置
optimization: {
minimizer: [
new OptimizeCssPlugin(),
new UglifyJsPlugin({
cache: true, //缓存
parallel: true, //并发打包
sourceMap: true //源码映射便于调试
})
]
},
//开一个本地服务
devServer: {
port: 3000, //端口号
progress: true, //进度条
contentBase: ‘./dist’, //指定目录运行服务
open: true //自动打开浏览器
},
entry: ‘./src/index.js’,
output: {
filename: ‘bundle.js’,
path: path.resolve(__dirname, ‘dist’)
},
// 模块配置
module: {
rules: [{
test: /\.(css|scss)$/,
use: [MiniCssExtractPlugin.loader, ‘css-loader’, ‘postcss-loader’, ‘sass-loader’]
}]
},
//插件配置
plugins: [
new HtmlWebpackPlugin({
template: ‘./src/index.html’, //原始文件
filename: ‘index.html’, //打包后的文件名称
hash: true, //hash
}),
new MiniCssExtractPlugin({
filename: ‘main.css’ //抽离出的css文件名称
})
]
}
package.json文件内容：
{
“name”: “webpack”,
“version”: “1.0.0”,
“main”: “index.js”,
“license”: “MIT”,
“scripts”: {
“dev”: “webpack –mode development && webpack-dev-server”,
“build”: “webpack –mode production”
},
“devDependencies”: {
“autoprefixer”: “^9.4.7”,
“css-loader”: “^2.1.0”,
“html-webpack-plugin”: “^3.2.0”,
“less”: “^3.9.0”,
“less-loader”: “^4.1.0”,
“mini-css-extract-plugin”: “^0.5.0”,
“node-sass”: “^4.11.0”,
“optimize-css-assets-webpack-plugin”: “^5.0.1”,
“postcss-loader”: “^3.0.0”,
“sass-loader”: “^7.1.0”,
“style-loader”: “^0.23.1”,
“uglifyjs-webpack-plugin”: “^2.1.1”,
“webpack”: “^4.29.4”,
“webpack-cli”: “^3.2.3”,
“webpack-dev-server”: “^3.1.14”,
“webpack-html-plugin”: “^0.1.1”
}
}
将ES6转化为ES5
step1: 打开src/index.js，输入：
const fn = () => {
console.log(‘丸子’);
}
fn ();
step2: 配置webpack.config.js文件：
将ES6转成ES5，需要babel-loader，配置规则为：
module.exports = {
//…
module: {
//…
{
test: /\.js$/,
use: {
loader: ‘babel-loader’,
options: {
presets: [‘@babel/preset-env’] // 根据目标浏览器自动转换为相应es5代码
}
}
}
}
};
step3: 安装插件：
yarn add babel-loader @babel/core @babel/preset-env -D
尝试运行： npm run dev, 成功！
转载请注明：XAMPP中文组官网 » 学习webpack4.x – ES6语法转化