- A+
所属分类:Web前端
背景
了解什么是webpack插件,在来看一下不能不知道的两个插件
- HtmlWebpackPlugin 有了这个插件,webpack执行后会自动帮我们在dist目录生成一个html文件,并且添加bundle.js的引用。
https://webpack.docschina.org/plugins/html-webpack-plugin - SplitChunksPlugin 这个插件可以协助我们在生成的bundle上进行更为精确的配置,比如node_modules下的模块单独打包到一个文件(方便缓存)等
开始
写2个按钮,点击分别加载页面1,页面2
//index.html <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> <title>Webpack App</title> <meta name="viewport" content="width=device-width,initial-scale=1" /> </head> <body> <h1>Hello webpack splitchunks</h1> <button id="btn1">页面1</button> <button id="btn2">页面2</button> </body> </html>
//入口脚本 window.addEventListener("load", function () { var btn1 = document.getElementById("btn1"); btn1.addEventListener("click", function () { import("./p1"); }); var btn2 = document.getElementById("btn2"); btn2.addEventListener("click", function () { import("./p2"); }); });
两个页面
//页面1 import { max } from "lodash"; console.log("p1 lodash", max);
//页面2 import { max } from "lodash"; console.log("p2 lodash", max);
//webpack 配置 const webpack = require("webpack"); const HtmlWebpackPlugin = require("html-webpack-plugin"); const path = require("path"); const config = { context: path.resolve(__dirname), mode: "production", optimization: { minimize: false, }, entry: "./main.js", target: ["web", "es5"], output: { clean: true, filename: "bundle.js", path: path.resolve(__dirname, "dist"), }, plugins: [ new HtmlWebpackPlugin({ template: "index.html", }), ], }; const compiler = webpack(config); compiler.run((err, stats) => { console.log(err); });
生成后的目录
//bundle.js 关键代码 var __webpack_exports__ = {}; console.log("hello"); window.addEventListener("load", function () { var btn1 = document.getElementById("btn1"); btn1.addEventListener("click", function () { Promise.all(/* import() */[__webpack_require__.e(891), __webpack_require__.e(751)]).then(__webpack_require__.bind(__webpack_require__, 751)); }); var btn2 = document.getElementById("btn2"); btn2.addEventListener("click", function () { Promise.all(/* import() */[__webpack_require__.e(891), __webpack_require__.e(291)]).then(__webpack_require__.bind(__webpack_require__, 291)); }); });
//751.bundle.js 关键代码 "use strict"; (self["webpackChunk"] = self["webpackChunk"] || []).push([[751],{ /***/ 751: /***/ (function(__unused_webpack_module, __webpack_exports__, __webpack_require__) { __webpack_require__.r(__webpack_exports__); /* harmony import */ var lodash__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__(891); /* harmony import */ var lodash__WEBPACK_IMPORTED_MODULE_0___default = /*#__PURE__*/__webpack_require__.n(lodash__WEBPACK_IMPORTED_MODULE_0__); console.log("p1 lodash", lodash__WEBPACK_IMPORTED_MODULE_0__.max); /***/ }) }]);
//291.bundle.js 关键代码 "use strict"; (self["webpackChunk"] = self["webpackChunk"] || []).push([[291],{ /***/ 291: /***/ (function(__unused_webpack_module, __webpack_exports__, __webpack_require__) { __webpack_require__.r(__webpack_exports__); /* harmony import */ var lodash__WEBPACK_IMPORTED_MODULE_0__ = __webpack_require__(891); /* harmony import */ var lodash__WEBPACK_IMPORTED_MODULE_0___default = /*#__PURE__*/__webpack_require__.n(lodash__WEBPACK_IMPORTED_MODULE_0__); console.log("p2 lodash", lodash__WEBPACK_IMPORTED_MODULE_0__.max); /***/ }) }]);
//891.bundle.js 关键代码(lodash模块代码) (self["webpackChunk"] = self["webpackChunk"] || []).push([[891],{ /***/ 891: /***/ (function(module, exports, __webpack_require__) { /* module decorator */ module = __webpack_require__.nmd(module); var __WEBPACK_AMD_DEFINE_RESULT__;/** * @license * Lodash <https://lodash.com/> * Copyright OpenJS Foundation and other contributors <https://openjsf.org/> * Released under MIT license <https://lodash.com/license> * Based on Underscore.js 1.8.3 <http://underscorejs.org/LICENSE> * Copyright Jeremy Ashkenas, DocumentCloud and Investigative Reporters & Editors */ ;(function() { /** Used as a safe reference for `undefined` in pre-ES5 environments. */ var undefined; /** Used as the semantic version number. */ var VERSION = '4.17.21'; /** Used as the size to enable large array optimizations. */ var LARGE_ARRAY_SIZE = 200; ......
总结
- 使用了异步加载模块,自动生成2个bundle(751、251)。异步模块好像一定是会拆分为一个新的文件(不确定)
- 2个模块都引用了lodash,所以lodash又单独拆出一个bundle(891)
- 进入页面加载
- 点击按钮1
- 点击按钮2
- 多看文档、多看文档、多看文档
https://webpack.docschina.org/plugins/split-chunks-plugin/