minor #6219 Point that route parameters are also Request attributes (sfdumi)

This PR was submitted for the 3.0 branch but it was merged into the 2.3 branch instead (closes #6219).

Discussion
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Point that route parameters are also Request attributes

Point that route parameters are also Request attributes

Commits
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08aae4e Point that route parameters are also Request attributes

Author: xabbuh

cookbook/routing/extra_information.rst

@@ -7,7 +7,7 @@ How to Pass Extra Information from a Route to a Controller
 Parameters inside the ``defaults`` collection don't necessarily have to
 match a placeholder in the route ``path``. In fact, you can use the
 ``defaults`` array to specify extra parameters that will then be accessible as
-arguments to your controller:
+arguments to your controller, and as attributes of the ``Request`` object:
 
 .. configuration-block::
 
@@ -52,12 +52,25 @@ arguments to your controller:
 
         return $collection;
 
-Now, you can access this extra parameter in your controller::
+Now, you can access this extra parameter in your controller, as an argument to the controller method::
 
+    use Symfony\Component\HttpFoundation\Request;
+    
     public function indexAction($page, $title)
     {
         // ...
     }
 
+Alternately, the title could be accessed through the ``Request`` object::
+
+    use Symfony\Component\HttpFoundation\Request;
+    
+    public function indexAction(Request $request, $page)
+    {
+        // ...
+        $title = $request->attributes->get('title');
+        // ...
+    }
+
 As you can see, the ``$title`` variable was never defined inside the route path,
-but you can still access its value from inside your controller.
+but you can still access its value from inside your controller, through the method's argument, or from the ``Request`` object's ``attributes`` bag.