Using route parameters

In the previous recipe, we defined a route and controller that responded to the /hello-world path. A route can add variables to the path, called route parameters, so that the controller can handle different URLs.

In this recipe, we will create a route that takes a user ID as a route parameter to display information about that user.

Getting started

This recipe uses the route created in the Defining a controller recipe to provide a custom page.

How to do it…

1. First, remove the src/Routing/RouteSubscriber.php file and mymodule.services.yml from the previous section and clear the Drupal cache, so it does not interfere with what we are about to do.
2. Next, edit routing.yml so that we can add a route parameter of user to the path:

     path: /hello-world/{user}

Route parameters are wrapped with an opening bracket ({) and a closing bracket (}).

3. Next, we will update the requirements key to specify that the user parameter...