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# Generate & Register a controller

$ drupal generate:controller [options]
$ gcn

module_name.example_controller:
  path: '/custom_path/{event_id}/{price_id}'
  defaults:
    _controller: '\Drupal\module_name\Controller\ExampleController::conteont'
  requirements:
    _permission: 'access content'
    _role: 'authenticated'
    
    
#https://www.drupal.org/docs/8/api/routing-system/introductory-drupal-8-routes-and-controllers-example

<?php

namespace Drupal\example\Controller;

use Drupal\Core\Controller\ControllerBase;

/**
 * An example controller.
 */
class ExampleController extends ControllerBase {

  /**
   * {@inheritdoc}
   */
  public function content() {
    $build = array(
      '#type' => 'markup',
      '#markup' => t('Hello World!'),
    );
    return $build;
  }

}

// See https://www.drupal.org/docs/8/api/routing-system/introductory-drupal-8-routes-and-controllers-example

You can already have access to several utilities service inside the a controller : 

- Current User
- Entity Manager
- URL
- Language
- Etc ...

See https://api.drupal.org/api/drupal/core!lib!Drupal!Core!Controller!ControllerBase.php/class/ControllerBase/8.2.x