php - ArrayCollection 的问题，必须管理传递给选择字段的“Doctrine\Common\Collections\ArrayCollection”类型的实体

Question

我想在我的 bdd 中添加一个新标签。使用 symfony，我确实做了：crud。在我的实体标签中，我有一个名为 Language 的列。它是与实体语言的多对一关系。

在我的表单中，我想让用户在两种语言之间进行选择，但我不想让他们选择多种语言。但是当我检查渲染时，我遇到了一个问题：

'必须管理传递给选择字段的“Doctrine\Common\Collections\ArrayCollection”类型的实体。也许您忘记将其保留在实体管理器中？

这是我的代码：

<?php

namespace App\Entity;

use App\Repository\TagRepository;
use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\Common\Collections\Collection;
use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity(repositoryClass=TagRepository::class)
 */
class Tag
{
    /**
     * @ORM\Id()
     * @ORM\GeneratedValue()
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255)
     */
    private $name;

    /**
     * @ORM\ManyToOne(targetEntity=Language::class, inversedBy="tag", cascade={"persist","remove"})
     */
    private $language;

    /**
     * @ORM\ManyToMany(targetEntity=Video::class, mappedBy="tags", cascade={"persist","remove"})
     */
    private $video;



    public function __construct()
    {
        $this->language= new ArrayCollection();
        $this->video = new ArrayCollection();
    }

    public function getId(): ?int
    {
        return $this->id;
    }

    public function getName(): ?string
    {
        return $this->name;
    }

    public function setName(string $name): self
    {
        $this->name = $name;

        return $this;
    }

    /**
     * @return Collection|Language[]
     */
    public function getLanguage(): Collection
    {
        return $this->language;
    }

    public function addLanguage(Language $language): self
    {
        if (!$this->language->contains($language)) {
            $this->language[] = $language;
            $language->setTag($this);
        }
        return $this;
    }

    public function removeLanguage(Language $language): self
    {
        if ($this->language->contains($language)) {
            $this->language->removeElement($language);
            // set the owning side to null (unless already changed)
            if ($language->getTag() === $this) {
                $language->setTag(null);
            }
        }

        return $this;
    }

    /**
     * @return Collection|Video[]
     */
    public function getVideo(): Collection
    {
        return $this->video;
    }

    public function addVideo(Video $video): self
    {
        if (!$this->video->contains($video)) {
            $this->video[] = $video;
        }

        return $this;
    }

    public function removeVideo(Video $video): self
    {
        if ($this->video->contains($video)) {
            $this->video->removeElement($video);
        }

        return $this;
    }

}

<?php

namespace App\Entity;

use App\Repository\LanguageRepository;
use Doctrine\Common\Collections\ArrayCollection;
use Doctrine\ORM\Mapping as ORM;

/**
 * @ORM\Entity(repositoryClass=LanguageRepository::class)
 */
class Language
{
    /**
     * @ORM\Id()
     * @ORM\GeneratedValue()
     * @ORM\Column(type="integer")
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255)
     */
    private $name;

    /**
     * @ORM\OneToMany(targetEntity=Tag::class, mappedBy="language", cascade={"persist","remove"})
     */
    private $tag;

    public function getId(): ?int
    {
        return $this->id;
    }

    public function getName(): ?string
    {
        return $this->name;
    }

    public function setName(string $name): self
    {
        $this->name = $name;

        return $this;
    }

    public function getTag(): ?Tag
    {
        return $this->tag;
    }

    public function setTag(?Tag $tag): self
    {
        $this->tag = $tag;

        return $this;
    }
}

还有我的表格：

<?php

namespace App\Form;

use App\Entity\Language;
use App\Entity\Tag;
use Symfony\Bridge\Doctrine\Form\Type\EntityType;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;

class TagType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add('name')
            ->add('language', EntityType::class, ['class'=>Language::class,
                'choice_label'=>'name',
                'multiple'=>false,
                'expanded' => true,])
        ;
    }

    public function configureOptions(OptionsResolver $resolver)
    {
        $resolver->setDefaults([
            'data_class' => Tag::class,
        ]);
    }
}

如果我将“多个”设置为 true，则没有问题，但用户可以选择 2 种语言，但我想让他们只选择一种语言。谢谢！

标签： phpsymfonydoctrine-ormdoctrine