A custom twig extension to truncate text while preserving HTML tags.
Add the library to your app's composer.json
:
"require": {
"dzango/twig-truncate-extension": "~1.0",
...
}
Add the extension to the Twig_Environment
:
use Dzango\Twig\Extension\Truncate;
$twig = new Twig_Environment(...);
$twig->addExtension(new Truncate());
The bundle exposes a truncate
twig filter, which can be applied to any string.
{{ "some ... very ... large ... text"|truncate }}
The truncate
filter accepts 4 arguments, all of which have sensible defaults and can therefore be ignored most of the time:
truncate($length = 100, $ending = '...', $exact = false, $considerHtml = true)
- length: the maximum number of characters to display, excluding any HTML markup (default
100
) - ending: The characters to be appended to the truncated string (default
...
) - exact: If set to true, the text may be cut off in the middle of a word. To avoid this, set this argument to false (default
false
) - considerHtml: If set to true, HTML markup will be ignored and left unchanged (default
true
)
Because the truncate
filter preserves HTML markup, it is perfectly able to handle rendered markdown content, as well as "raw" content (as rendered by the raw
filter). For example, assuming your app has enabled a markdown
twig filter for parsing markdown content, the following is fully supported:
{{ "some ... very ... long ... markdown text"|markdown|raw|truncate }}
To use this extension in a symfony2 project, you have 2 options:
# app/config/config.yml
services:
dzango.twig.truncate_extension:
class: Dzango\Twig\Extension\Truncate
tags:
- { name: twig.extension }
The Dzango/TwigTruncateBundle will register the extension for you as a service.
- http://alanwhipple.com/2011/05/25/php-truncate-string-preserving-html-tags-words/ for the truncation logic