为什么我在运行 npx run dev 时会出现找不到模块错误？

Question

为什么我在运行 npx run dev 时会出现找不到模块错误？

在运行'npx run dev'之前

我处理了这个

运行 npm init 命令 webpack webpack-cli 安装 配置 webpack.config.js 设置 package.json 节点升级 创建 client.jsx WordRelay.jsx 组件文件创建等

webpack.config.js

const path = require('path');

module.exports = {
    name:'wordrelay-setting',
    mode:'development',
    devtool:'eval',
    resolve:{
        extensions:['.js','.jsx']
    },

    entry:{
        app:['./client']
    }, // 입력

    output: {
        path:path.join(__dirname,'dist'),
        filename:'app.js'
    },  // 출력

};

package.json

{
  "name": "lecture",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "dev": "webpack"
  },
  "author": "hyun",
  "license": "ISC",
  "dependencies": {
    "react": "^16.8.6",
    "react-dom": "^16.8.6"
  },
  "devDependencies": {
    "webpack": "^4.37.0",
    "webpack-cli": "^3.3.6"
  }
}

和github： https://github.com/hyunsokstar/react_game_prac2

Answer 1

你运行 webpack，但你不让 webpack 知道它应该采取什么配置。所以它将使用默认配置运行。其中entry 设置为src/index.js。您需要运行 webpack 并将其指向您的配置文件（文件名不正确，请修复它）。

另一个问题是您在代码中使用了jsx，但没有使用babel 将jsx 编译为js。所以你需要在你的项目中添加babel。

最后一个问题是client.jsx 文件中有一些错误语法。

package.json

{
  "name": "lecture",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "dev": "webpack --config webpack.config.js"
  },
  "author": "hyun",
  "license": "ISC",
  "dependencies": {
    "react": "^16.8.6",
    "react-dom": "^16.8.6"
  },
  "devDependencies": {
    "@babel/core": "^7.5.5",
    "babel-loader": "^8.0.6",
    "babel-preset-react-app": "^9.0.0",
    "webpack": "^4.37.0",
    "webpack-cli": "^3.3.6"
  },
  "babel": {
    "presets": [
      "react-app"
    ]
  }
}

webpack.config.js

const path = require('path');
process.env.NODE_ENV='development';

module.exports = {
    name:'wordrelay-setting',
    mode:'development',
    devtool:'eval',
    resolve:{
        extensions:['.js','.jsx']
    },

    entry:{
        app:['./client']
    }, // 입력

    output: {
        path:path.join(__dirname,'dist'),
        filename:'app.js'
    },  // 출력

    module: {
        rules: [
          {
            test: /\.(js|jsx)$/,
            exclude: /node_modules/,
            use: {
              loader: "babel-loader"
            }
          }
        ]
    }
}

client.jsx

const React = require('react');
const ReactDom = require('react-dom');

const WordRelay = require('./WordRelay')
React.render(<WordRelay />, document.querySelector('#root'));

原答案

当您使用此命令时npx run dev。您正在执行 run 模块。这就是你得到错误的原因。正确的命令应该是

npm run dev

Difference between npx and npm?