如何使用 webpack 从 node_modules 加载静态 CSS 文件的示例？

Question

我不知道如何使用 webpack 从 node_modules 库中加载任何 CSS，例如我已经安装了传单并且每次加载 leaflet/dist/leaflet.css 的尝试都失败了。

您能否举例说明如何从 node_modules 加载静态样式？

下面是我当前的 webpack 配置。另外我正在使用extract-text-webpack-plugin 和sass-loader 我的项目scss 文件运行良好，我也有css-loader，我是否需要解析静态css 文件或向stylePathResolves 添加一些内容？

//require('leaflet/dist/leaflet.css');

var ExtractTextPlugin = require("extract-text-webpack-plugin");
var webpack = require("webpack");
var path = require('path');

var stylePathResolves = (
  'includePaths[]=' + path.resolve('./') + '&' +
  'includePaths[]=' + path.resolve('./node_modules')
)

module.exports = {
  entry: ".js/app.js",
  output: {
    path: "./static/js",
    filename: "app.js"
  },
  module: {
    loaders: [{
        test: /\.jsx?$/,
        exclude: /node_modules/,
        loader: 'babel'
      }, {
        test: /\.scss$/,
        loader: ExtractTextPlugin.extract(
          'style',
          'css' + '!sass?outputStyle=expanded&' + stylePathResolves
        )
      }
    ]
  },
  plugins: [new ExtractTextPlugin("app.css")]
};

在哪里加载leaflet.css，注释掉require('leaflet/dist/leaflet.css')给我以下错误：

home/myproj/node_modules/leaflet/dist/leaflet.css:3
.leaflet-map-pane,
^

SyntaxError: Unexpected token .

Answer 1

对于遇到类似问题的用户，我已经采取了一些步骤来使其正常工作，我不确定这种平衡方式。

1. npm install file-loader --save
2. 在主app.js中添加import 'leaflet/dist/leaflet.css';
3. 通过以下方式更改 webpack.config.js：

添加css-loader 以摆脱SyntaxError: Unexpected token .，然后添加file-loader 并匹配文件以摆脱Uncaught Error: Cannot find module "./images/layers.png"：

module.exports = {
  entry: "./web/static/js/app.js",
  output: {
    path: "./priv/static/js",
    filename: "app.js"
  },
  module: {
    loaders: [{
      test: /\.jsx?$/,
      exclude: /node_modules/,
      loader: 'babel'
    }, {
      test: /\.scss$/,
      loader: ExtractTextPlugin.extract(
        'style',
        'css' + '!sass?outputStyle=expanded&' + stylePathResolves
      )
    }, {
      test: /\.css$/,
      loader: "style-loader!css-loader"
    }, {
      test: /\.(png|jpg|jpeg|gif|svg|woff|woff2|ttf|eot)$/,
      loader: 'file-loader'
    }]
  },
  plugins: [new ExtractTextPlugin("app.css")]
};

一开始我从一些例子中得到了这个配置，我还不是 100% 清楚为什么我使用 ExtractTextPlugin 来加载 scss 以及与 css-loader 的相关性，如果我也使用 ExtractTextPlugin 可能会更连贯在这部分，也许有人知道并且可以进行代码审查？但我的解决方案是有效的，我可以进一步工作。

Answer 2

我必须这样做：

npm install --save-dev style-loader css-loader file-loader

如果我没有为图像配置文件加载器，我得到：

ERROR in ./node_modules/leaflet/dist/images/layers-2x.png 1:0
Module parse failed: Unexpected character '�' (1:0)
You may need an appropriate loader to handle this file type.
(Source code omitted for this binary file)
 @ ./node_modules/leaflet/dist/leaflet.css (./node_modules/css-loader!./node_modules/leaflet/dist/leaflet.css) 7:8888-8921
 @ ./node_modules/leaflet/dist/leaflet.css
 @ ./src/view/component/RouteMap.js
 @ ./src/index.js

ERROR in ./node_modules/leaflet/dist/images/layers.png 1:0
Module parse failed: Unexpected character '�' (1:0)
You may need an appropriate loader to handle this file type.
(Source code omitted for this binary file)
 @ ./node_modules/leaflet/dist/leaflet.css (./node_modules/css-loader!./node_modules/leaflet/dist/leaflet.css) 7:8716-8746
 @ ./node_modules/leaflet/dist/leaflet.css
 @ ./src/view/component/RouteMap.js
 @ ./src/index.js

ERROR in ./node_modules/leaflet/dist/images/marker-icon.png 1:0
Module parse failed: Unexpected character '�' (1:0)
You may need an appropriate loader to handle this file type.
(Source code omitted for this binary file)
 @ ./node_modules/leaflet/dist/leaflet.css (./node_modules/css-loader!./node_modules/leaflet/dist/leaflet.css) 7:9975-10010
 @ ./node_modules/leaflet/dist/leaflet.css
 @ ./src/view/component/RouteMap.js
 @ ./src/index.js

您还必须将 CSS 文件导入您的 index.js 或 main.js（或任何您的主 JS 文件）。否则，您会收到一条错误消息，指出 module.exports is read-only。

import 'leaflet/dist/leaflet.css';

更新后的webpack.config.jssn-p 是：

{
    ...
    module: {
        rules: [
            { test: /\.css$/, use: ["style-loader","css-loader"] },
            { test: /\.(png|svg|jpe?g|gif|woff2?|ttf|eot)$/, use: [ 'file-loader' ] },
        ],
    },