# srcset
> Parse and stringify the HTML `![]()
` [srcset](https://www.smashingmagazine.com/2013/08/webkit-implements-srcset-and-why-its-a-good-thing/) attribute.
Can be useful if you're creating a build-tool.
## Install
```
$ npm install srcset
```
## Usage
How an image with `srcset` might look like:
```html
```
Then have some fun with it:
```js
const srcset = require('srcset');
const parsed = srcset.parse('banner-HD.jpg 2x, banner-phone.jpg 100w');
console.log(parsed);
/*
[
{
url: 'banner-HD.jpg',
density: 2
},
{
url: 'banner-phone.jpg',
width: 100
}
]
*/
parsed.push({
url: 'banner-super-HD.jpg',
density: 3
});
const stringified = srcset.stringify(parsed);
console.log(stringified);
/*
banner-HD.jpg 2x, banner-phone.jpg 100w, banner-super-HD.jpg 3x
*/
```
## API
### .parse(string, options?)
Parse the HTML `![]()
` [srcset](http://mobile.smashingmagazine.com/2013/08/21/webkit-implements-srcset-and-why-its-a-good-thing/) attribute.
Accepts a “srcset” string and returns an array of objects with the possible properties: `url` (always), `width`, `height`, and `density`.
#### string
Type: `string`
A “srcset” string.
#### options
Type: `object`
##### strict
Type: `boolean`\
Default: `false`
When enabled, an invalid “srcset” string will cause an error to be thrown. When disabled, a best effort will be made to parse the string, potentially resulting in invalid or nonsensical output.
### .stringify(SrcSetDefinitions, options?)
Stringify `SrcSetDefinition`s. Accepts an array of `SrcSetDefinition` objects and returns a “srcset” string.
#### srcsetDescriptors
Type: `array`
An array of `SrcSetDefinition` objects. Each object should have a `url` field and may have `width`, `height` or `density` fields. When the `strict` option is `true`, only `width` or `density` is accepted.
#### options
Type: `object`
##### strict
Type: `boolean`
Default: `false`
Enable or disable validation of the SrcSetDefinitions. When true, invalid input will cause an error to be thrown. When false, a best effort will be made to stringify invalid input, likely resulting in invalid srcset value.
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