How to use dependency injection in custom Symfony services?

To use dependency injection in custom Symfony services, follow these steps:

Define your custom service in a services configuration file (usually services.yml or services.xml) in the config directory of your Symfony application. You can define the service with its class name and any dependencies it requires.

Example services.yml configuration:

services:
    App\Service\MyCustomService:
        class: App\Service\MyCustomService
        arguments:
            - '@doctrine.orm.entity_manager'

Create the custom service class in your application's src/Service directory (or a similar location). Make sure to define any constructor arguments in the class and assign them to class properties.

Example custom service class:

namespace App\Service;

use Doctrine\ORM\EntityManagerInterface;

class MyCustomService
{
    private $entityManager;

    public function __construct(EntityManagerInterface $entityManager)
    {
        $this->entityManager = $entityManager;
    }
    
    // Add your service logic here
}

Now you can use your custom service in your controllers or other services by injecting it via the constructor or through a setter method.

Using the service in a controller:

namespace App\Controller;

use App\Service\MyCustomService;
use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;

class SomeController extends AbstractController
{
    private $myCustomService;

    public function __construct(MyCustomService $myCustomService)
    {
        $this->myCustomService = $myCustomService;
    }
    
    public function someAction()
    {
        // Use the custom service
        $data = $this->myCustomService->getData();
        
        return $this->json($data);
    }
}

By following these steps, you can leverage dependency injection to easily manage and utilize custom services in your Symfony application.