如何让Symfony 4项目中的所有URL都包含_locale

# config/routes.yaml

app:
    resource: '../src/Controller/'
    type: annotation
    prefix: '/{_locale}'

// src/Controller/DefaultController.php

use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
use Symfony\Component\Routing\Annotation\Route;

class DefaultController extends AbstractController
{
    /**
     * @Route("/", name="homepage")
     */
    public function index()
    {
        // ...
    }

    /**
     * @Route("/about", name="about")
     */
    public function about()
    {
        // ...
    }
}

{# templates/default/index.html.twig #}

<a href="{{ path('homepage', {'_locale': app.request.locale}) }}">Home</a>
<a href="{{ path('about', {'_locale': app.request.locale}) }}">About</a>

# config/packages/translation.yaml

framework:
    default_locale: en