npm install css-loader
var css = require("css!./file.css");
// => returns css code from file.css, resolves imports and url(...)
@import
and url(...)
are interpreted like require()
and will be resolved by the css-loader.
Good loaders for requiring your assets are the file-loader
and the url-loader which you should specify in your config (see below).
To be combatible to existing css files:
url(image.png)
=>require("./image.png")
url(~module/image.png)
=>require("module/image.png")
This webpack config can load css files, embed small png images as Data Urls and jpg images as files.
module.exports = {
module: {
loaders: [
{ test: /\.css$/, loader: "style-loader!css-loader" },
{ test: /\.png$/, loader: "url-loader?limit=100000&mimetype=image/png" },
{ test: /\.jpg$/, loader: "file-loader" }
]
}
};
For urls that start with a /
, the default behavior is to not translate them:
url(/image.png)
=>url(/image.png)
If a root
query parameter is set, however, it will be prepended to the url
and then translated:
With a config like:
loaders: [
{ test: /\.css$/, loader: "style-loader!css-loader?root=." },
...
]
The result is:
url(/image.png)
=>require("./image.png")
If you don't want to process the images but rather want to transform the URLs use this parameter
If a skipRequireAndAddPath
query parameter is set, it will be prepended to the url and assets won't be added to webpack bundle:
With a config like:
loaders: [
{ test: /\.css$/, loader: "style-loader!css-loader?skipRequireAndAddPath=app/images" },
...
]
The result is:
url(/image.png)
=>require("app/images/image.png")
To include SourceMaps set the sourceMap
query param.
require("css-loader?sourceMap!./file.css")
I. e. the extract-text-webpack-plugin can handle them.
The query parameter importLoaders
allow to configure which loaders should be applied to @import
ed resources.
importLoaders
(int): That many loaders after the css-loader are used to import resources.
Examples:
require("style-loader!css-loader?importLoaders=1!autoprefixer-loader!...")
// => imported resources are handled this way:
require("css-loader?importLoaders=1!autoprefixer-loader!...")
require("style-loader!css-loader!stylus-loader!...")
// => imported resources are handled this way:
require("css-loader!...")
By default the css-loader minimizes the css if specified by the module system.
In some cases the structural minification is destructive to the css, so you can disable it with the disableStructuralMinification
query parameter. require("css-loader?disableStructuralMinification!./file.css")
You can also disable or enforce minification with the minimize
query parameter.
require("css-loader?minimize!./file.css")
(enforced)
require("css-loader?-minimize!./file.css")
(disabled)
You cannot use minimize with SourceMaps.