您可能需要适当的加载程序来处理此文件类型，当前未配置任何加载程序来处理此文件

Question

我正在尝试将webpack与我的react项目集成在一起，并且收到以下错误消息。

at androidx.room.testing.MigrationTestHelper.loadSchema(MigrationTestHelper.java:320)
at androidx.room.testing.MigrationTestHelper.createDatabase(MigrationTestHelper.java:152)
at com.company.companyapp.MigrationTest.migrate1To2(MigrationTest.java:32)

我试图在这里找到一些答案，但无济于事。看来问题出在我的index.js页面上，我尝试渲染整个应用程序

You may need an appropriate loader to handle this file type, currently no loaders are configured to process this file.

这是我的package.json文件：

ReactDOM.render(<Main />, document.getElementById('root'));

这是我的webpack.config.build.js文件：

{
"name": "app",
"version": "0.1.0",
"private": true,
"dependencies": {
"@material-ui/core": "^4.4.2",
"@material-ui/icons": "^4.4.1",
"axios": "^0.19.0",
"babel-core": "^6.26.3",
"material-ui": "^0.20.2",
"react": "^16.10.2",
"react-activity": "^1.2.2",
"react-dom": "^16.10.2",
"react-dropzone": "^10.1.10",
"react-redux": "^7.1.1",
"react-responsive-carousel": "^3.1.51",
"react-router": "^5.1.2",
"react-router-dom": "^5.1.2",
"react-router-flux": "^1.0.0",
"react-scripts": "3.1.1",
"react-tap-event-plugin": "^3.0.3",
"redux": "^4.0.4",
"redux-persist": "^6.0.0",
"redux-promise": "^0.6.0",
"redux-thunk": "^2.3.0",
"serve": "^11.2.0",
"superagent": "^5.1.0"
},
"scripts": {
"start": "PORT=8080 react-scripts start",
"build": "webpack --env.API_URL=https://neighbor-hood.herokuapp.com --config 
webpack.config.build.js",
"test": "react-scripts test",
"eject": "react-scripts eject"
},
"eslintConfig": {
"extends": "react-app"
},
"browserslist": {
"production": [
  ">0.2%",
  "not dead",
  "not op_mini all"
],
"development": [
  "last 1 chrome version",
  "last 1 firefox version",
  "last 1 safari version"
]
},
"devDependencies": {
"webpack": "^4.39.1",
"webpack-cli": "^3.3.10"
}
}

任何我的.babelrc文件：

const webpack = require('webpack'); 
module.exports = (env) => {
const envKeys = Object.keys(env).reduce((prev, next) => {
prev[`process.env.${next}`] = JSON.stringify(env[next]);
return prev;
}, {});

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


return {
plugins: [
  new webpack.DefinePlugin(envKeys)
]
};
};

这是我的index.js文件：

.babelrc
{
"presets": ["env", "react","@babel/preset-env"],
"plugins": [
    "transform-class-properties"
]
}

不确定这意味着什么...（可能已经回答了）

Answer 1

您的直接问题就在这里。 --config之后有回车符或换行符。

"build": "webpack --env.API_URL=https://neighbor-hood.herokuapp.com --config 
webpack.config.build.js",

尝试一下。

"build": "webpack --env.API_URL=https://neighbor-hood.herokuapp.com --config webpack.config.build.js",