Symfony 2 Catchable Fatal Error: Object of class UserCategory could not be converted to string

Question

I try to put in place a system of categories . I love that my users can tag with categories . So I put a Array Collection and a " ManyToMany " but it does not work and whatever I do I get this error " Catchable Fatal Error : Object of class Shootngo \ CoreBundle \ Entity \ UserCategory couldn't be converted to string".

If someone could help me, i think i will not have hairs if i continue to search a solution...

           $userCategories = new ArrayCollection();

        foreach ($form->getCategories()->getLibCategory() as $category) {
            $userCategories->add($category);
        }

        $user->addCategory($userCategories);

My FormType :

            ->add('category', CollectionType::class, array(
            'entry_type' => UserCategoryType::class,
            'allow_add'    => true,
        ))

My View :

<div class="form-group">
   <label class="col-sm-4 control-label">Catégories<span class="text-danger">*</span></label>
    <div class="col-sm-6">
      {{ form_errors(form.category) }}
      <ul id="category-list" data-prototype="{{ form_widget(form.category.vars.prototype)|e }}">
        {% for cat in form.category %}
           {{ form_errors(cat) }}
           <div class="form-group">
              {{ form_widget(cat,{'attr' : {'class' : 'form-control', 'placeholder' : "", 'data-parsley-required' : 'data-parsley-required'}}) }}
           </div>
        {% endfor %}
      </ul>
      <a href="#" id="add-another-category">Add another category</a>
    </div>

thank in advance ! Christophe

Answer 1

you need to add a method to

Shootngo\CoreBundle\Entity\UserCategory

entity class...

public function __toString()
{
  return 'My string version of UserCategory'; // if you have a name property you can do $this->getName();
}

that way when the select options are being generated php automatically uses the __toString() method to convert the Entity Object into text...