layout: default title: Attributes Extension
The AttributesExtension allows HTML attributes to be added from within the document.
The basic syntax was inspired by Kramdown's Attribute Lists feature.
You can assign any attribute to a block-level element. Just directly prepend or follow the block with a block inline attribute list. That consists of a left curly brace, optionally followed by a colon, the attribute definitions and a right curly brace:
> A nice blockquote
{: title="Blockquote title"}
{#id .class}
## Header
As with a block-level element you can assign any attribute to a span-level elements using a span inline attribute list, that has the same syntax and must immediately follow the span-level element:
This is *red*{style="color: red"}.
This extension is bundled with league/commonmark. This library can be installed via Composer:
composer require league/commonmark
See the installation section for more details.
Configure your Environment as usual and simply add the AttributesExtension:
use League\CommonMark\CommonMarkConverter;
use League\CommonMark\Environment;
use League\CommonMark\Extension\Attributes\AttributesExtension;
// Obtain a pre-configured Environment with all the CommonMark parsers/renderers ready-to-go
$environment = Environment::createCommonMarkEnvironment();
// Add the extension
$environment->addExtension(new AttributesExtension());
// Set your configuration if needed
$config = [
// ...
];
// Instantiate the converter engine and start converting some Markdown!
$converter = new CommonMarkConverter($config, $environment);
echo $converter->convertToHtml('# Hello World!');