Wie erstellt man ein einfaches Formular in Symfony 2?

<?php
// file: AppBundle/Entity/Employee.php

namespace AppBundle\Entity;

use AppBundle\Entity\Role;
use Doctrine\ORM\Mapping as ORM;
use Doctrine\Common\Collections\ArrayCollection;

/**
 * Employee entity.
 *
 * @ORM\Table(name="employee")
 * @ORM\Entity(repositoryClass="AppBundle\Entity\EmployeeRepository")
 */
class Employee extends Person {
  /**
   * @var ArrayCollection
   *
   * @ORM\ManyToMany(targetEntity="AppBundle\Entity\Role")
   * @ORM\JoinTable(name="employees_roles",
   *    joinColumns={@ORM\JoinColumn(name="employee_id", referencedColumnName="id")},
   *    inverseJoinColumns={@ORM\JoinColumn(name="role_id", referencedColumnName="id")}
   * )
   */
  protected $roles;

  /**
   * @var string
   *
   * @ORM\Column(type="string", length=255, nullable=true)
   */
  protected $salary;

  /**
   * Constructor.
   */
  public function __construct() {
    parent::__construct();
    $this->roles = new ArrayCollection();
  }

  /**
   * Get roles as array of strings.
   *
   * @return array
   */
  public function getRoles() {
    $roleNames = [];
    foreach ($this->roles as $role) {
      $roleNames[] = $role->getName();
    }
    return $roleNames;
  }

  /**
   * Get roles ass ArrayCollection.
   *
   * @return ArrayCollection
   */
  public function getRolesCollection() {
    return $this->roles;
  }

  /**
   * Returns TRUE if employee has ROLE_ADMIN.
   *
   * @return bool
   */
  public function isAdmin() {
    return in_array('ROLE_ADMIN', $this->getRoles(), TRUE);
  }

  /**
   * Set roles.
   *
   * @param ArrayCollection $roles
   * @return Employee
   */
  public function setRolesCollection($roles) {
    $this->roles = $roles;
    return $this;
  }

  /**
   * Add roles
   *
   * @param Role $roles
   * @return Employee
   */
  public function addRolesCollection(Role $roles) {
    $this->roles[] = $roles;

    return $this;
  }

  /**
   * Remove roles
   *
   * @param Role $roles
   */
  public function removeRolesCollection(Role $roles) {
    $this->roles->removeElement($roles);
  }

  /**
   * Set salary
   *
   * @param string $salary
   * @return Employee
   */
  public function setSalary($salary) {
    $this->salary = $salary;

    return $this;
  }

  /**
   * Get salary
   *
   * @return string
   */
  public function getSalary() {
    return $this->salary;
  }
}

<?php
// file: AppBundle/Entity/Role.php

namespace AppBundle\Entity;

use Doctrine\ORM\Mapping as ORM;
use Symfony\Bridge\Doctrine\Validator\Constraints\UniqueEntity;
use Symfony\Component\Security\Core\User\UserInterface;

/**
 * Role
 *
 * @ORM\Table(name="role")
 * @ORM\Entity(repositoryClass="AppBundle\Entity\RoleRepository")
 * @UniqueEntity("name")
 */
class Role implements BaseEntityInterface {
  /**
   * @var integer
   *
   * @ORM\Column(name="id", type="integer")
   * @ORM\Id
   * @ORM\GeneratedValue(strategy="AUTO")
   */
  private $id;

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

  /**
   * Get id
   *
   * @return integer
   */
  public function getId() {
    return $this->id;
  }

  /**
   * Set name
   *
   * @param string $name
   * @return Role
   */
  public function setName($name) {
    $this->name = $name;

    return $this;
  }

  /**
   * Get name
   *
   * @return string
   */
  public function getName() {
    return $this->name;
  }
}

<?php
// file: AppBundle/Form/Type/EmployeeType.php

namespace AppBundle\Form\Type;

use AppBundle\Entity\Employee;
use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\OptionsResolver\OptionsResolver;

class EmployeeType extends AbstractType {
  /**
   * @var Employee
   */
  protected $loggedInUser;

  /**
   * Constructor.
   *
   * @param Employee $loggedInUser
   */
  public function __construct(Employee $loggedInUser) {
    $this->loggedInUser = $loggedInUser;
  }

  /**
   * Used to build the form.
   *
   * @param FormBuilderInterface $builder
   * @param array $options
   */
  public function buildForm(FormBuilderInterface $builder, array $options) {
    $builder
      ->add('firstName', 'text')
      ->add('lastName', 'text')
      ->add('email', 'text')
      ->add(
        'rolesCollection', 'entity',
        [
          'class' => 'AppBundle\Entity\Role',
          'property' => 'name',
          'multiple' => TRUE,
          'expanded' => TRUE,
          'label' => 'Roles',
          'disabled' => !$this->loggedInUser->isAdmin(),
        ]
      )
      ->add(
        'salary', 'money',
        [
          'required' => FALSE,
          'currency' => 'EUR',
          'disabled' => !$this->loggedInUser->isAdmin(),
        ]
      )
      ->add(
        'activeFrom', 'date',
        [
          'input' => 'datetime',
          'widget' => 'choice',
          'disabled' => !$this->loggedInUser->isAdmin(),
        ]
      )
      ->add(
        'activeTo', 'date',
        [
          'required' => FALSE,
          'input' => 'datetime',
          'widget' => 'choice',
          'placeholder' => '',
          'disabled' => !$this->loggedInUser->isAdmin(),
        ]
      )
      ->add('save', 'submit', ['label' => 'Save employee']);
  }

  /**
   * Returns the name of this type.
   *
   * @return string The name of this type
   */
  public function getName() {
    return 'app_employee';
  }

  /**
   * Configures form's options.
   *
   * @param OptionsResolver $resolver
   */
  public function configureOptions(OptionsResolver $resolver) {
    $resolver->setDefaults(
      [
        'data_class' => 'AppBundle\Entity\Employee',
      ]
    );
  }
}

  /**
   * @var string
   *
   * @ORM\Column(name="email", type="string", length=255)
   * @Assert\NotBlank() 
   * @Assert\Email()
   */
  private $email;

/**
   * Opens edit page for employee with passed $id.
   *
   * @Route("/admin/edit_employee/{id}", name="edit_employee", defaults={"id" = -1})
   * @Template
   *
   * @param $id
   * @param Request $request
   * @return array
   */
  public function editEmployeeAction($id, Request $request) {
    /** @var Employee $loggedInUser */
    $loggedInUser = $this->getUser();
    /** @var EmployeeRepository $employeeRepository */
    $employeeRepository = $this->getDoctrine()->getRepository('AppBundle:Employee');
    if ($id > -1) {
      // Editing employee
      /** @var Employee $employee */
      $employee = $employeeRepository->find($id);
    } else {
      // Adding new employee
      /** @var Employee $employee */
      $employee = new Employee();
    }

    $form = $this->createForm(new EmployeeType($loggedInUser), $employee);
    $form->handleRequest($request);

    if ($form->isValid()) {
      $employeeRepository->persistEntity($employee);
      return $this->redirectToRoute('table_employee');
    }

    return [
      'loggedInUser' => $loggedInUser,
      'employee' => $employee,
      'form' => $form->createView(),
    ];
  }

if ($form->isValid()) {
  $employeeRepository->persistEntity($employee);
  return $this->redirectToRoute('table_employee');
}

{# file: AppBundle/Resources/views/Employee/editEmployee.html.twig #}

{% block body %}
  {{ form(form) }}
{% endblock %}

# Twig Configuration
twig:
    form:
        resources: ['bootstrap_3_horizontal_layout.html.twig']