Webpack 4 – 简单的 js 功能在打包文件后不起作用 [英] Webpack 4 – simple js function not working after bundled files

问题描述

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

I’m relatively new to webpack. I’m trying to make a simple architecture work, but can’t seem to find out what’s wrong. I’m going to try to summarize my code:

package.json 文件:

package.json file:

"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:

webpack.config.js file:

"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:

backend.src.js file:

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

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

functions-syncsystem.js 文件:

functions-syncsystem.js file:

"use strict";

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

index.html 文件(简单的纯 html，我在其中导入捆绑文件以进行测试):

index.html file (simple, plain html where i´m importing the the bundled files in order to test):

(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测试架构而创建的简单 js 函数.控制台给了我这样的错误消息:

When I run the index, the css file loads fine, the js file also loads fine, but it doesn´t seem to recognize the simple js function I created in order to test the architecture. Console gives me an error message like this:

未捕获的引用错误:未定义 webpackDebugTest

Uncaught ReferenceError: webpackDebugTest is not defined

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

I’ve also tried changing the functions-syncsystem.js file to the following:

"use strict";

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

module.exports = {
    webpackDebugTest: webpackDebugTest
};

并且在捆绑文件中，我可以找到以下代码:e.exports={webpackDebugTest:function(){alert("Webpack test - inside function")}

And in the bundled file, I can find the following code: e.exports={webpackDebugTest:function(){alert("Webpack test - inside function")}

它仍然在控制台面板上返回相同的错误消息.

And it still returns me that same error message on the console panel.

任何人都可以发现我的使用有什么问题?

Anyone can detect what could be the issue with my usage?

推荐答案

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

为了使用import"，你需要安装这个

in order to use "import" you need to install this

npm i @babel/register --save 

在您的入口点文件之上

require("@babel/register")

这篇关于Webpack 4 – 简单的 js 功能在打包文件后不起作用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！