javascript - webpack 无法启动 react 项目
问题描述
我正在学习使用 webpack 开发一个 react 项目,但是我无法在本地启动本地服务。它报告以下错误。
ERROR in ./src/index.js 5:16
Module parse failed: Unexpected token (5:16)
You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file. See https://webpack.js.org/concepts#loaders
| import App from './App';
|
> ReactDOM.render(<App />, document.getElementById('root'));
|
我怀疑这是babel编译的问题,但是我配置了babel-loader,但是还是不行。这个问题我google了很久,还是没找到问题。你能帮助我吗?谢谢!
这是我的配置文件。
// webpack.common.js
const path = require('path');
const commonConfig = {
entry: [
'babel-polyfill',
'../src/index.js'
],
output: {
path: path.resolve(__dirname, 'dist'),
filename: 'bundle.js'
},
plugins: [
new HtmlWebpackPlugin({
template: path.resolve(__dirname, 'dist/index.html')
})
],
module: {
rules: [{
test: /\.(jsx?|tsx?)$/,
loader: 'babel-loader',
exclude: /node_modules/,
}]
}
};
module.exports = commonConfig;
// webpack.dev.js
const merge = require('webpack-merge');
const commonConfig = require('./webpack.common.js');
const path = require('path');
const devConfig = merge(commonConfig, {
mode: 'development',
devServer: {
contentBase: path.join(__dirname, 'dist'),
compress: true,
port: 3000
}
})
module.exports = devConfig;
// package.json
"scripts": {
"test": "echo \"Error: no test specified\" && exit 1",
"start": "webpack-dev-server",
},
"devDependencies": {
"@babel/core": "^7.11.4",
"@babel/preset-env": "^7.11.0",
"@babel/preset-react": "^7.10.4",
"babel-core": "^6.26.3",
"babel-loader": "^8.1.0",
"babel-polyfill": "^6.26.0",
"babel-preset-env": "^1.7.0",
"babel-preset-es2015": "^6.24.1",
"babel-preset-react": "^6.24.1",
"html-webpack-plugin": "^4.3.0",
"webpack": "^4.44.1",
"webpack-cli": "^3.3.12",
"webpack-dev-server": "^3.11.0"
},
"dependencies": {
"react": "^16.13.1",
"react-dom": "^16.13.1"
// .babelrc
{
"presets": ["env", "react"]
}
解决方案
我发现问题出在哪里。我没有在 的脚本中webpack.dev.js
为命令指定文件,并且在进行以下更改后它起作用了。npm run start
package.json
"scripts": {
"start": "webpack-dev-server --config webpack/webpack.dev.js",
},
推荐阅读
- r - 如何使用 R 在特定时期获取 twitter 用户的时间线。是否有任何 API 问题?
- react-native - 如何修复反应原生 webview 错误代码 -2
- javascript - 无法在 Discord.js v12 上获取实际成员列表
- ios - Flutter:使用`ARCHS`设置构建目标`Pods-Runner`的架构:(``)
- python - 在 Python 中检测 Deflate 流的结束
- sql - 遍历用户并检查他们在过去 12 个月内是否存在
- vue.js - 如何在 Vue 中使用 v-for 更改数组中单个对象的输入值?
- javascript - React-Hooks:如何调用 useState 返回的函数
- python - 如何在没有列洗牌的情况下从 Dask Dataframe 制作新的 pandas Dataframe?
- python - 如何在python中检查程序的运行时间