Symfony3 ::處理ManyToMany關係

Question

我試圖保存用戶和類別之間的ManyToMany關係。其實我試圖用給定的用戶來保存我的類別，但這不起作用。

形式

$builder->add('name') 
     ->add('users', EntityType::class, array(
      'label' => 'Benutzer', 
      'class' => 'AppBundle\Entity\User', 
      'multiple' => true, 
      'expanded' => true, 
      'required' => false, 
      'choice_label' => function (User $user) { 
       return $user->getUsername(); 
      } 
     )) 
     ->add('submit', SubmitType::class, array(
      'label' => 'Speichern' 
     )); 

---

表單處理程序

public function onSuccess(Request $request) 
{ 
    // Get category from form 
    $category = $this->getForm()->getData(); 

    // Redirect to parent category when setted 
    if ($this->parent) { 
     $category->setParent($this->parent); 
     $response = new RedirectResponse($this->router->generate('categories.view', [ 
      'category' => $this->parent->getId() 
     ])); 
    } else { 
     // Build new redirect response 
     $response = new RedirectResponse($this->router->generate('categories.view', [ 
      'category' => $category->getId() 
     ])); 
    } 

    try { 
     // Save category in database 
     $this->em->merge($category); 
     $this->em->flush(); 
    } catch (ORMException $ex) { 
     throw $ex; 
    } 

    return $response; 
} 

Answer 1

也許你必須先反序列化實體類$？

$detachedCategory = unserialize($category); 
$this->em->merge($detachedCategory); 
$this->em->flush(); 

我發現關於這個鏈接： How to manage deserialized entities with entity manager?

不知道如果是這樣的答案，但你可能希望做更多的研究。