npm i -D css-loader
The css-loader
interprets @import
and url()
as ES Modules (import
) and resolves them
⚠️ Assets (url()
) need to loaded separately by e.g the file-loader or the url-loader, which you should specify in your config (webpack.config.js
) (see below)
file.js
import css from './file.css';
webpack.config.js
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: [ 'style-loader', 'css-loader' ]
}
]
}
}
Name | Type | Default | Description |
---|---|---|---|
url |
{Boolean} |
true |
Enable/Disable url() resolving |
import |
{Boolean} |
true |
Enable/Disable @import resolving |
minimize |
{Boolean} |
false |
Enable/Disable Minification |
sourceMap |
{Boolean} |
false |
Enable/Disable Source Maps |
To disable url()
resolving by css-loader
set the option to false
.selector {
declaration: url('./path/to/image.png');
}
import CSS__URL__0 from './path/to/image.png';
export default `
.selector {
declaration: url(${CSS__URL__0});
}
`
To disable url()
resolving by css-loader
set the option to false
webpack.config.js
{
loader: 'css-loader',
options: {
url: false
}
}
webpack.config.js
{
loader: 'css-loader',
options: {
url: /filter/
}
}
webpack.config.js
{
loader: 'css-loader',
options: {
url (url) {
return /filter/.test(url)
}
}
}
@import './path/to/import.css';
import CSS__IMPORT__0 from './path/to/import.css';
export default `
.css {
color: red;
}
`
To disable @import
resolving by css-loader
set the option to false
webpack.config.js
{
loader: 'css-loader',
options: {
import: false
}
}
webpack.config.js
{
loader: 'css-loader',
options: {
import: /filter/
}
}
webpack.config.js
{
loader: 'css-loader',
options: {
import (url) {
return /filter/.test(url)
}
}
}
webpack.config.js
{
loader: 'css-loader',
options: {
minimize: true
}
}
⚠️ They are not enabled by default because they expose a runtime overhead and increase in bundle size (JS source maps do not). In addition to that relative paths are buggy and you need to use an absolute public path which includes the server URL.
webpack.config.js
{
loader: 'css-loader',
options: {
sourceMap: true
}
}
The following webpack.config.js
can load CSS files, embed small PNG/JPG/GIF/SVG images as well as fonts as Data URLs and copy larger files to the output directory.
webpack.config.js
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: [ 'style-loader', 'css-loader' ]
},
{
test: /\.(png|jpg|gif|svg|eot|ttf|woff|woff2)$/,
loader: 'url-loader',
options: {
limit: 10000
}
}
]
}
}
For production builds it's recommended to extract the CSS from your bundle being able to use parallel loading of CSS/JS resources later on. This can be achieved by using the extract-text-webpack-plugin to extract the CSS when running in production mode.
webpack.config.js
const env = process.env.NODE_ENV
const ExtractTextPlugin = require('extract-text-webpack-plugin')
module.exports = {
module: {
rules: [
{
test: /\.css$/,
use: env === 'production'
? ExtractTextPlugin.extract({
fallback: 'style-loader',
use: [ 'css-loader' ]
})
: [ 'style-loader', 'css-loader' ]
},
]
},
plugins: env === 'production'
? [
new ExtractTextPlugin({
filename: '[name].css'
})
]
: []
}
![]() Juho Vepsäläinen |
![]() Joshua Wiens |
![]() Michael Ciniawsky |
![]() Alexander Krasnoyarov |