Services, dependency injection, and service containers

发表于

创建Services

  1. .info.yml

  2. .services.yml

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    services:
      service_example.example_service:
        class: Drupal\service_example\ServiceExampleService

  3. src/Service.php

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    class ServiceExampleService {
        protected $service_example_value;
        /**
         * When the service is created, set a value for the example variable.
         */
        public function __construct() {
            $this->service_example_value = 'Student';
        }
        /**
         * Return the value of the example variable.
         */
        public function getServiceExampleValue() {
            return $this->service_example_value;
        }
    }

使用services

  1. class method

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    1.1 Retrieve the service using the Container in the create() function.
    1.2 Pass the service to the __construct() function.
    1.3 Store the service as a class variable.
    /**
     * @var \Drupal\service_example\ServiceExampleService
     */
    protected $serviceExampleService;
    /**
     * {@inheritdoc}
     */
    public function __construct(ServiceExampleService $serviceExampleService) {
        $this->serviceExampleService = $serviceExampleService;
    }
    /**
     * {@inheritdoc}
     */
    public static function create(ContainerInterface $container) {
        return new static(
            $container->get('service_example.example_service')
        );
    }
    public function simple_example() {
      return [
          '#markup' => $this->serviceExampleService->getServiceExampleValue()
      ];
    }

  2. static method

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    $serviceExampleService = \Drupal::service('service_example.example_service');
    $value = $serviceExampleService->getServiceExampleValue();

参考资料

Services, dependency injection, and service containers