如何在Symfony中显示相关实体的下拉列表？

use Symfony\Bridge\Doctrine\Form\Type\EntityType;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;

class YourFormType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            // Other form fields
            ->add('relatedEntity', EntityType::class, [
                'class' => 'App\Entity\RelatedEntity',
                'choice_label' => 'name', // 根据实际情况设置显示的字段
                'placeholder' => 'Select a related entity', // 可选，设置默认提示文本
            ]);
    }
}

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

class YourController extends AbstractController
{
    /**
     * @Route("/your-route", name="your_route")
     */
    public function yourAction(Request $request)
    {
        $form = $this->createForm(YourFormType::class);

        $form->handleRequest($request);
        if ($form->isSubmitted() && $form->isValid()) {
            // 处理表单提交逻辑
        }

        return $this->render('your_template.html.twig', [
            'form' => $form->createView(),
        ]);
    }
}

{# your_template.html.twig #}

<form method="post" action="{{ path('your_route') }}">
    {{ form_widget(form) }}
    <button type="submit">Submit</button>
</form>