Webpack：移动webpack / react文件的位置后，npm start“找不到模块：错误：无法解析...”

Question

我的项目正在运行，我可以在使用 Chrome 时在 localhost:8080 上查看我的网页。 我试图学习一些东西，所以我将所有文件都放在一个名为“dir copy”的文件夹中，而不仅仅是 dir。 当一切都如我所愿时，我将所有文件移回“目录”并关闭浏览器。 当我再次尝试运行npm start 时，我收到了这个错误输出

---

来自 npm start 的输出

Jacob:Name_html Jacob$ npm start

> Name@ start Dir/Name/Name_html
> node ./node_modules/webpack-dev-server/bin/webpack-dev-server.js

ℹ ｢wds｣: Project is running at http://localhost:8080/
ℹ ｢wds｣: webpack output is served from /
ℹ ｢wds｣: Content not from webpack is served from Dir/Name/Name_html
✖ ｢wdm｣: Hash: a0d05c0fdc6ff660f346
Version: webpack 4.35.0
Time: 1985ms
Built at: 06/28/2019 3:29:15 AM
      Asset     Size  Chunks             Chunk Names
./bundle.js  908 KiB    main  [emitted]  main
Entrypoint main = ./bundle.js
[1] multi (webpack)-dev-server/client?http://localhost ./src/index.jsx 40 bytes {main} [built]
[./es6/Banner.js] 1010 bytes {main} [built]
[./es6/Footer.js] 320 bytes {main} [built]
[./es6/Header.js] 387 bytes {main} [built]
[./es6/HomePageServices.js] 3.4 KiB {main} [built]
[./es6/NavBar.js] 689 bytes {main} [built]
[./node_modules/react-dom/cjs/react-dom.development.js] 768 KiB {main} [built]
[./node_modules/react-dom/index.js] 1.33 KiB {main} [built]
[./node_modules/react/cjs/react.development.js] 62.3 KiB {main} [built]
[./node_modules/react/index.js] 190 bytes {main} [built]
[./node_modules/scheduler/cjs/scheduler.development.js] 23.3 KiB {main} [built]
[./node_modules/scheduler/index.js] 198 bytes {main} [built]
[./node_modules/webpack-dev-server/client/index.js?http://localhost] (webpack)-dev-server/client?http://localhost 4.29 KiB {main} [built]
[./node_modules/webpack/hot sync ^\.\/log$] (webpack)/hot sync nonrecursive ^\.\/log$ 160 bytes {main} [built]
[./src/index.jsx] 561 bytes {main} [built]
    + 2 hidden modules

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './overlay' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 10:14-34
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './socket' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 8:13-32
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './utils/createSocketUrl' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 20:22-56
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './utils/log' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 12:15-37
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './utils/reloadApp' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 18:16-44
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve './utils/sendMessage' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 16:18-48
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx

ERROR in ./node_modules/react-dom/cjs/react-dom.development.js
Module not found: Error: Can't resolve 'object-assign' in 'Dir/Name/Name_html/node_modules/react-dom/cjs'
 @ ./node_modules/react-dom/cjs/react-dom.development.js 19:14-38
 @ ./node_modules/react-dom/index.js
 @ ./src/index.jsx
 @ multi ./src/index.jsx

ERROR in ./node_modules/react/cjs/react.development.js
Module not found: Error: Can't resolve 'object-assign' in 'Dir/Name/Name_html/node_modules/react/cjs'
 @ ./node_modules/react/cjs/react.development.js 18:14-38
 @ ./node_modules/react/index.js
 @ ./src/index.jsx
 @ multi ./src/index.jsx

ERROR in ./node_modules/react-dom/cjs/react-dom.development.js
Module not found: Error: Can't resolve 'prop-types/checkPropTypes' in 'Dir/Name/Name_html/node_modules/react-dom/cjs'
 @ ./node_modules/react-dom/cjs/react-dom.development.js 20:21-57
 @ ./node_modules/react-dom/index.js
 @ ./src/index.jsx
 @ multi ./src/index.jsx

ERROR in ./node_modules/react/cjs/react.development.js
Module not found: Error: Can't resolve 'prop-types/checkPropTypes' in 'Dir/Name/Name_html/node_modules/react/cjs'
 @ ./node_modules/react/cjs/react.development.js 19:21-57
 @ ./node_modules/react/index.js
 @ ./src/index.jsx
 @ multi ./src/index.jsx

ERROR in ./node_modules/react-dom/cjs/react-dom.development.js
Module not found: Error: Can't resolve 'scheduler/tracing' in 'Dir/Name/Name_html/node_modules/react-dom/cjs'
 @ ./node_modules/react-dom/cjs/react-dom.development.js 22:14-42
 @ ./node_modules/react-dom/index.js
 @ ./src/index.jsx
 @ multi ./src/index.jsx

ERROR in (webpack)-dev-server/client?http://localhost
Module not found: Error: Can't resolve 'strip-ansi' in 'Dir/Name/Name_html/node_modules/webpack-dev-server/client'
 @ (webpack)-dev-server/client?http://localhost 6:16-37
 @ multi (webpack)-dev-server/client?http://localhost ./src/index.jsx
ℹ ｢wdm｣: Failed to compile.

---

这些是一些无效的方法

Adding modules: ["src", "node_modules"] to webpack.config.js

Deleting node_modules and running npm install again

---

src/index.jsx

import React from 'react';
import ReactDOM from 'react-dom';
import someSelfCreatedComponents from ../es6/SelfCreatedComponents

const Content = () => {
    return (
        <React.Fragment>
            <Header />
            <Banner />
            <MoreThings />
            <Footer />
        </React.Fragment>
    )
}

ReactDOM.render (
    <Content />,
    document.getElementById('Content')
)

webpack.config.js

module.exports = {
	entry: [
		'./src/index.jsx'	
	],
	output: {
		filename: './bundle.js'	//File that all react gets compioled into
	},
	module: {
		rules: [
			{
				exclude: /node_modules/,
				use: [
					'babel-loader'
				]
			}
		]
	},
	resolve: {
		extensions: ['js', '.jsx']
	}
}

package.json

{
  "name": "Name",
  "version": "",
  "description": "",
  "main": "index.js",
  "scripts": {
    "start": "node ./node_modules/webpack-dev-server/bin/webpack-dev-server.js"
  },
  "dependencies": {
    "@babel/preset-es2015": "^7.0.0-beta.53",
    "babel-core": "^6.26.3",
    "babel-plugin-transform-object-rest-spread": "^6.26.0",
    "babel-preset-env": "^1.7.0",
    "babel-preset-es2015": "^6.24.1",
    "babel-preset-react": "^6.24.1",
    "babel-preset-stage-1": "^6.24.1",
    "react": "^16.8.6",
    "react-dom": "^16.8.6",
    "webpack-cli": "^3.3.5",
    "webpack-dev-server": "^3.7.2"
  },
  "devDependencies": {
    "@babel/core": "^7.4.5",
    "@babel/preset-env": "^7.4.5",
    "@babel/preset-react": "^7.0.0",
    "babel-loader": "^8.0.6",
    "webpack": "^4.35.0"
  }
}

.babelrc

{
	"presets": ["@babel/preset-react", "@babel/preset-env"]
}

index.html

<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8" />
    <title>Name</title>
    
    <link rel="stylesheet" type="text/css" href="css/Main.css">

    <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">
    <meta name="viewport" content="width=device-width, initial-scale=1.00, maximum-scale=1.10, minimum-scale=0.80">

  </head>
  <body>
    <div id='Content'></div>
    <script src='bundle.js'></script>
  </body>
</html>

文件排列

---

更新

我阅读了 Saheed 在下面的答案中发布的 blog article，并尝试通过删除 webpack.config.js 文件并将文件缩减为

来修复我的项目

module.exports = {
	module: {
		rules: [
			{
				exclude: /node_modules/,
				use: [
					'babel-loader'
				]
			}
		]
	},
	resolve: {
		extensions: ['js', '.jsx']
	}
	
}

两次尝试后，我仍然收到相同的错误。

Answer 1

如果您想避免核选项，请确保 .js 包含在 webpack 的已解析扩展中。

这里的问题可能是js之前缺少.造成的：

module.exports = {
    // ...
    resolve: {
        extensions: ['.js', '.jsx']
    }
}

Answer 2

找到了解决方案，但它并不能完全回答我的代码出了什么问题，下面有一条评论试图回答问题所在。

我删除了我的 .babelrc、package-lock.json、webpack.config.js、package.json 和 node 模块，然后关注this tutorial for setting up react, babel7, and webpack4 from scratch，因为它是我能找到的最有用的一个

这里是它的摘要

---

他们从

开始

mkdir default && cd default && yarn init -y

然后我安装了以下模块

npm install @babel/core @babel/cli @babel/preset-env @babel/preset-react babel-loader -D

并将下面的代码复制粘贴到.babelrc

文件中

{
  "presets": ["@babel/preset-env", "@babel/preset-react"]
}

---

我安装了更多模块

npm install webpack webpack-cli webpack-dev-server html-webpack-plugin html-webpack-template -D

并将下面的代码复制并粘贴到 webpack.config.js 中（稍作调整，因为我收到了错误Uncaught Error: Target container is not a DOM element.）

const webpack = require('webpack');
const HtmlWebpackPlugin = require('html-webpack-plugin');
const HtmlWebpackTemplate = require('html-webpack-template');
const path = require('path');

const config = {
  entry: './src/index.js',
  output: {
    path: path.resolve(__dirname, './dist'),
    filename: 'bundle.js',
  },
  module: {
    rules: [
      {
        test: /\.(js|jsx)$/,
        use: 'babel-loader',
        exclude: /node_modules/,
      },
    ],
  },
  resolve: {
    extensions: ['.js', '.jsx'],
  },
};

module.exports = config;

npm install react react-dom

而且我没有更改我的 index.js，但是教程中列出的那个是

import React from "react";
import ReactDOM from "react-dom";

function App() {
  return (
    <div>
      <h1>Hello blog readers</h1>
    </div>
  );
}

const rootElement = document.getElementById("app");
ReactDOM.render(<App />, rootElement);

Answer 3

就我而言，我正在处理打字稿项目。

我使用的是 ts-loader 版本 8.2.0，我升级到版本 ts-loader@9.2.5 并且错误消失了。