javascript - Webpack 4 – 简单的 js 功能在捆绑文件后不起作用

Question

我对 webpack 还比较陌生。我试图让一个简单的架构发挥作用，但似乎无法找出问题所在。我将尝试总结我的代码:

package.json 文件:

"devDependencies": {
"@babel/preset-env": "^7.8.3",
"babel-loader": "^8.0.6",
"babel-preset-es2015": "^6.24.1",
"bootstrap": "^4.4.1",
"clean-webpack-plugin": "^3.0.0",
"css-loader": "^3.4.2",
"file-loader": "^5.0.2",
"html-loader": "^0.5.5",
"html-webpack-plugin": "^3.2.0",
"jest": "^24.9.0",
"jest-cli": "^24.9.0",
"jquery": "^3.4.1",
"mini-css-extract-plugin": "^0.9.0",
"node-sass": "^4.13.1",
"optimize-css-assets-webpack-plugin": "^5.0.3",
"popper.js": "^1.16.1",
"sass-loader": "^8.0.2",
"style-loader": "^1.1.3",
"webpack": "^4.41.5",
"webpack-cli": "^3.3.10",
"webpack-dev-server": "^3.10.1",
"webpack-merge": "^4.2.2"

}

webpack.config.js 文件:

"use strict";
const path = require("path");
const merge = require("webpack-merge"); 
const HtmlWebpackPlugin = require('html-webpack-plugin'); 
const { CleanWebpackPlugin } = require("clean-webpack-plugin");
const MiniCssExtractPlugin = require('mini-css-extract-plugin'); 
const OptimizeCssAssetsPlugin = require('optimize-css-assets-webpack-plugin'); 
const TerserPlugin = require("terser-webpack-plugin"); 


module.exports = {
mode: "production",
devtool: "none", 
entry: {
    "backend":"./src/backend.src.js"
}, 
output: {
    filename: "[name].bundle.js",
    path: path.resolve(__dirname, "dist")
},
optimization: {
    minimize: true,
    concatenateModules: true,
    namedModules: true,
    minimizer: [
        new TerserPlugin(),
        new OptimizeCssAssetsPlugin()
    ]
}, 
plugins: [
    new HtmlWebpackPlugin({
        minify: {
            collapseWhitespace: true,
            removeComments: true
        }
    }),
   new MiniCssExtractPlugin({filename: "styles-[name].bundle.css"}), 
   new CleanWebpackPlugin()
],
module: {
    rules: [
        //CSS.
        {
            test: /\.css$/,
            use: [
                MiniCssExtractPlugin.loader,
                "css-loader"
            ] 
        },

        //SASS.
        {
            test: /\.scss$/,
            use: [
                MiniCssExtractPlugin.loader,
                "css-loader",
                "sass-loader"
            ]
        }


        //JS (transpile to es5)
        {
            test: /\.js$/,
            use: [
                {
                    loader: "babel-loader",
                    options: {
                        presets: ["@babel/preset-env"]       
                    }
                }
            ]
        },

        //HTML
        {
            test: /\.html$/,
            use: [
                "html-loader"
            ]
        },

        //Files
        {
            test: /\.(svg|png|jpg|jpeg|gif)$/,
            use: {
                loader: "file-loader",
                options: {
                    name: "[name].[hash].[ext]",
                    outputPath: "imgs",
                    esModule: false
                }
            }

        }
    ]
}
};

backend.src.js 文件:

"use strict";
import '../app_styles/styles-backend.css';

import { webpackDebugTest } from '../app_js/functions-syncsystem.js';

functions-syncsystem.js 文件:

"use strict";

export function webpackDebugTest()
{
    alert("Webpack test - inside function");
}

index.html 文件(简单、纯 html，我导入捆绑文件以进行测试):

(simple html)
<script>
    webpackDebugTest();
</script>
(simple html)

当我运行索引时，css 文件加载正常，js 文件也加载正常，但它似乎无法识别我为了测试架构而创建的简单 js 函数。控制台给我一条错误消息，如下所示:

Uncaught ReferenceError :webpackDebugTest 未定义

我还尝试将functions-syncsystem.js 文件更改为以下内容:

"use strict";

function webpackDebugTest()
{
    alert("Webpack test - inside function");
}

module.exports = {
    webpackDebugTest: webpackDebugTest
};

在捆绑文件中，我可以找到以下代码:e.exports={webpackDebugTest:function(){alert("Webpack 测试 - 函数内部")}

它仍然在控制台面板上向我返回相同的错误消息。

任何人都可以检测到我的使用可能存在什么问题吗？

Answer 1

entry: {
    backend:"./src/backend.src.js"
}, 

为了使用“导入”，您需要安装这个

npm i @babel/register --save 

在入口点文件之上

require("@babel/register")