We will first instantiate a Zend_Markup_Renderer_Html object using the Zend_Markup::factory() method. This will also create a Zend_Markup_Parser_Bbcode object which will be added to the renderer object.

Afther that, we will use the render() method to convert a piece of BBCode to HTML.

// Creates instance of Zend_Markup_Renderer_Html,
// with Zend_Markup_Parser_BbCode as its parser
$bbcode = Zend_Markup::factory('Bbcode');

echo $bbcode->render('[b]bold text[/b] and [i]cursive text[/i]');
// Outputs: '<strong>bold text</strong> and <em>cursive text</em>'

This time, we will do exactly the same as above, but with more complicated BBCode markup.

$bbcode = Zend_Markup::factory('Bbcode');

$input = <<<EOT
[list]
[*]Zend Framework
[*]Foobar
[/list]
EOT;

echo $bbcode->render($input);
/*
Should output something like:
<ul>
<li>Zend Framework</li>
<li>Foobar</li>
</ul>
*/

Besides simply parsing and rendering markup such as BBCode, Zend_Markup is also able to handle incorrect input. Most BBCode processors are not able to render all input to XHTML valid output. Zend_Markup corrects input that is nested incorrectly, and also closes tags that were not closed:

$bbcode = Zend_Markup::factory('Bbcode');

echo $bbcode->render('some [i]wrong [b]sample [/i] text');
// Note that the '[b]' tag is never closed, and is also incorrectly
// nested; regardless, Zend_Markup renders it correctly as:
// some <em>wrong <strong>sample </strong></em><strong> text</strong>