axios 没有定义

Question

我正在使用 axios 使用 React.js 构建一个简单的天气应用程序。我刚刚完成了代码，但是有一个问题。当我启动该应用程序时，它根本不工作，我看到一个参考错误，上面写着 axios is not defined 。

这是我的 webpack.config.js 文件：

 module.exports = {
    entry: './public/app/app.jsx',
    output: {
        path: __dirname,
        filename: './public/js/bundle.js'
    },
    externals: ['axios'],
    resolve: {
        root: __dirname,
        alias: {
            OpenWeatherMap: 'public/components/OpenWeatherMap.jsx',
            Main: 'public/components/Main.jsx',
            Nav: 'public/components/Nav.jsx',
            Weather: 'public/components/Weather.jsx',
            WeatherForm: 'public/components/WeatherForm.jsx',
            WeatherMessage: 'public/components/WeatherMessage.jsx',
            About: 'public/components/About.jsx'
        },
        extensions: ['', '.js', '.jsx']
    },
    module: {
        loaders: [{
            loader: 'babel-loader',
            query: {
                presets: ['react','es2015', 'stage-0']
            },
            test: /\.jsx?$/,
            exclude: /(node_modules|bower_components)/
        },{
            loader: 'json-loader',
            test: /\.json?$/
        }]
    }
};

和 package.json 文件：

 {
  "name": "weather",
  "version": "1.0.0",
  "description": "Simple Weather App",
  "main": "ext.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "Milad Fattahi",
  "license": "ISC",
  "dependencies": {
    "axios": "^0.16.1",
    "express": "^4.15.3",
    "json": "^9.0.6",
    "json-loader": "^0.5.4",
    "react": "^15.5.4",
    "react-dom": "^15.5.4",
    "react-router": "^4.1.1",
    "react-router-dom": "^4.1.1"
  },
  "devDependencies": {
    "babel-core": "^6.5.1",
    "babel-loader": "^6.2.2",
    "babel-preset-es2015": "^6.5.0",
    "babel-preset-react": "^6.5.0",
    "babel-preset-stage-0": "^6.24.1",
    "webpack": "^1.12.13"
  }
}

原文由 Milad Fattahi 发布，翻译遵循 CC BY-SA 4.0 许可协议

Answer 1

我知道这可能看起来很明显，但请确保文件顶部有对正确 axios 的引用或安装它 https://www.npmjs.com/package/axios

 <script src="https://unpkg.com/axios/dist/axios.min.js"></script>

原文由 itReverie 发布，翻译遵循 CC BY-SA 3.0 许可协议

Answer 2

我忘了导入 axios。我添加到脚本的顶部：

 import axios from 'axios';

我也忘了安装axios。我使用以下命令通过 npm 安装了 axios：

 npm i axios --global
// --global flags will save you the stress of insstalling axios again.

那解决了我的错误。

原文由 pamekar 发布，翻译遵循 CC BY-SA 4.0 许可协议