問題描述

我有一部分代碼，我通過依賴注入注入了兩個服務(wù) $checker 和 $paginator.它完美地工作:

I have a part of code where I'm injecting two services $checker and $paginator by dependency injection. It works perfectly:

public function index(Request $request, Paginator $paginator, Checker $checker)
    {
        $result = ['a', 'b', 'c', 'd', 'e', 'f', 'g'];
        $partialResult = $paginator->getPartial($result, 0, 3);
        $checker->isValid('A');
        var_dump("test");
        die;
    }

在services.yaml文件的配置下面:

   paginator:
        public: true
        class: 'AppHelperPaginator'

    checker:
        public: true
        class: 'AppHelperChecker'
        arguments:
         $paginator: '@paginator'

但由于某些原因我想通過方法注入服務(wù):

But I'd like to inject for some reasons service by method:

$checker = $this->container->get('checker');

但它不起作用.在以前的 Symfony 版本中，像 3.4 那樣.

But it doesn't work. In previous versions Symfony like 3.4 it used to.

我收到一個錯誤:

未找到服務(wù)checker":事件雖然它存在于應(yīng)用程序的容器中，但AppControllerDefaultController"中的容器是一個較小的服務(wù)定位器，它只知道http_kernel"、parameter_bag"、request_stack"、路由器"、會話"和樹枝"服務(wù).嘗試改用依賴注入.

Service "checker" not found: event though it exists in the app's container, the container inside "AppControllerDefaultController" is a smaller service locator that only knows about the "http_kernel", "parameter_bag", "request_stack", "router", "session", and "twig" services. Try using dependency injection instead.

我該如何解決這個問題?

How should I solve this?

推薦答案

你需要添加你的依賴項(xiàng) 服務(wù)定位器可以找到它們.

You need to add your dependencies so the service locator can find them.

將方法 getSubscribedServices() 添加到您的控制器類:

Add a method getSubscribedServices() to your controller class:

public static function getSubscribedServices()
{
    return array_merge(
        parent::getSubscribedServices(),
        [
            'checker' => Checker::class,
        ]
    );
}

如果你的控制器類擴(kuò)展了 AbstractController 你可以簡單地做:

If your controller class extends AbstractController you can simply do:

$this->get('checker');

如果您想在其他類型的類中執(zhí)行此操作(例如不擴(kuò)展AbstractController 的服務(wù))，那么您需要聲明您的服務(wù)實(shí)現(xiàn)了ServiceSubscriberInterface.

If you want to do it in another type of class (e.g. a service that doesn't extend AbstractController), then you need to declare that your service implements the ServiceSubscriberInterface.

use SymfonyContractsServiceServiceSubscriberInterface;
use PsrContainerContainerInterface;

class FooService implements ServiceSubscriberInterface {

    public function __construct(ContainerInterface $locator)
    {
        $this->locator = $locator;
    }

    public static function getSubscribedServices() { /* same as before */ }

    public function get($service)
    {
        return $this->locator->get($service);
    }
}

...并且您可以像之前在控制器中那樣做同樣的事情.

... and you would be able to do the same than you in the controller earlier.

這篇關(guān)于如果我沒有/無法使用 DI 注入服務(wù)，我如何直接從容器中獲取服務(wù)?的文章就介紹到這了，希望我們推薦的答案對大家有所幫助，也希望大家多多支持html5模板網(wǎng)！