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Symfony2 – Franz Jordán 2011
The headers property is a HeaderBag object with several useful methods for reading and
mutating the Response headers. The header names are normalized so that using Content-
Type is equivalent to content-type or even content_type.
The Request Object
Besides the values of the routing placeholders, the controller also has access to
the Request object when extending the base Controller class:
$request = $this->getRequest();
$request->isXmlHttpRequest(); // is it an Ajax request?
$request->getPreferredLanguage(array('en', 'fr'));
$request->query->get('page'); // get a $_GET parameter
$request->request->get('page'); // get a $_POST parameter
Like the Response object, the request headers are stored in a HeaderBag object and are easily
accessible.
Final Thoughts
Whenever you create a page, you'll ultimately need to write some code that contains the logic for
that page. In Symfony, this is called a controller, and it's a PHP function that can do anything it
needs in order to return the final Response object that will be returned to the user.
To make life easier, you can choose to extend a base Controller class, which contains
shortcut methods for many common controller tasks. For example, since you don't want to put
HTML code in your controller, you can use the render() method to render and return the
content from a template.
In other chapters, you'll see how the controller can be used to persist and fetch objects from a
database, process form submissions, handle caching and more.
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