Symfony2 standalone Form component example

sf2_form.php

<?php
/**
 * @author Nicolas Clavaud <[email protected]>
 * http://n.clavaud.free.fr/blog/index.php?article31/symfony2-standalone-form-component-tutorial
 */

namespace Me\MyApp;

use Symfony\Component\ClassLoader\UniversalClassLoader;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilder;
use Symfony\Component\Form\FormFactory;
use Symfony\Component\Form\Extension\Core\CoreExtension;

use Symfony\Component\EventDispatcher\EventDispatcher;

use Symfony\Component\Templating\TemplateNameParser;
use Symfony\Component\Templating\TemplateNameParserInterface;
use Symfony\Component\Templating\TemplateReference;
use Symfony\Component\Templating\Loader\FilesystemLoader;
use Symfony\Component\Templating\PhpEngine;

use Symfony\Component\Translation\MessageSelector;
use Symfony\Component\Translation\Translator;
use Symfony\Component\Translation\TranslatorInterface;

use Symfony\Bundle\FrameworkBundle\Templating\Helper\FormHelper;
use Symfony\Bundle\FrameworkBundle\Templating\Helper\TranslatorHelper;

// validation
use Symfony\Component\Form\Extension\Validator\ValidatorExtension;
use Symfony\Component\Validator\Validator;
use Symfony\Component\Validator\Mapping\ClassMetadata;
use Symfony\Component\Validator\Mapping\ClassMetadataFactory;
use Symfony\Component\Validator\Mapping\Loader\StaticMethodLoader;
use Symfony\Component\Validator\ConstraintValidatorFactory;
use Symfony\Component\Validator\Constraints as Constraints;

/**
 * Load and configure autoloader
 * @see http://symfony.com/doc/2.0/cookbook/tools/autoloader.html
 */
require_once 'Symfony/Component/ClassLoader/UniversalClassLoader.php';

$loader = new UniversalClassLoader();
$loader->register();
$loader->registerNamespace('Symfony', __DIR__.'/');

/**
 * Parameters
 */
$locale = null;

/**
 * Entity
 */
class Message
{

    public $sender;
    public $recipient;
    public $message;

    // validation
    public static function loadValidatorMetadata(ClassMetadata $metadata)
    {
      $metadata->addPropertyConstraint('sender', new Constraints\NotBlank());
      $metadata->addPropertyConstraint('sender', new Constraints\Email());
      $metadata->addPropertyConstraint('recipient', new Constraints\NotBlank());
      $metadata->addPropertyConstraint('recipient', new Constraints\Email());
      $metadata->addPropertyConstraint('message', new Constraints\NotBlank());
      $metadata->addPropertyConstraint('message', new Constraints\MinLength(10));
    }

}

/**
 * Form Class
 * @see http://symfony.com/doc/2.0/book/forms.html#creating-form-classes
 */
class MessageType extends AbstractType
{

  public function buildForm(FormBuilder $builder, array $options)
  {
      $builder
        ->add('sender', 'email')
        ->add('recipient', 'email')
        ->add('message', 'textarea');
  }

  public function getName()
  {
      return 'message';
  }

  public function getDefaultOptions(array $options)
  {
      return array(
          'data_class' => 'Me\MyApp\Message',
      );
  }

}

/**
 * Template name parser
 * @see Symfony\Bundle\FrameworkBundle\Tests\Templating\Helper\Fixtures\StubTemplateNameParser
 *
 * Needed to load the templates used for rendering form items.
 */
class StubTemplateNameParser implements TemplateNameParserInterface
{
    private $root;

    private $rootTheme;

    public function __construct($root, $rootTheme)
    {
        $this->root = $root;
        $this->rootTheme = $rootTheme;
    }

    public function parse($name)
    {

      list($bundle, $controller, $template) = explode(':', $name);

      if ($template[0] == '_') {
          $path = $this->rootTheme.'/Custom/'.$template;
      } elseif ($bundle === 'TestBundle') {
          $path = $this->rootTheme.'/'.$controller.'/'.$template;
      } else {
          $path = $this->root.'/'.$controller.'/'.$template;
      }

      return new TemplateReference($path, 'php');

    }
}

/**
 * Create an entity
 */
$message = new Message();
$message->sender = '[email protected]';

/**
 * Build a form from a form factory
 */
$form_factory = new FormFactory(array(
    new CoreExtension(),
    // validation
    new ValidatorExtension(
        new Validator(
            new ClassMetadataFactory(
                new StaticMethodLoader()
            ),
            new ConstraintValidatorFactory()
        )
    )
));
$form = $form_factory->create(new MessageType(), $message);

/**
 * Create a PHP template engine
 */
$root = realpath(__DIR__ . '/Symfony/Bundle/FrameworkBundle/Resources/views');
$rootTheme = realpath(__DIR__ . '/Symfony/Bundle/FrameworkBundle/Resources');
$templateNameParser = new StubTemplateNameParser($root, $rootTheme);
$loader = new FilesystemLoader(array());
$engine = new PhpEngine($templateNameParser, $loader);

/**
 * This helper will help rendering form items
 */
$form_helper = new FormHelper($engine, array(
    'FrameworkBundle:Form',
));

/**
 * Bind it to the engine
 */
$engine->setHelpers(array(
    $form_helper,
    new TranslatorHelper(new Translator($locale, new MessageSelector())),
));

/**
 * Bind submitted data
 */
$submitted = false;
$valid = null;
if (isset($_POST[$form->getName()])) {
    $form->bind($_POST[$form->getName()]);
    $submitted = true;
    // validation
    if ($valid = $form->isValid()) {
        // you may want to redirect at this state
    }
}

/**
 * Create the form view
 */
$form_view = $form->createView();

/**
 * Now, it's time to render HTML!
 */
header('Content-type: text/html; charset=utf-8');
?>
<!DOCTYPE html>
<html>
    <body>
        <form action="" method="post"
            <?php print $form_helper->enctype($form_view) ?>
            novalidate="novalidate">
            <?php print $form_helper->widget($form_view) ?></div>
            <input type="submit" />
        </form>

        <?php if ($submitted && $valid) : ?>
        <p><strong>Submitted form is valid.</strong></p>
        <?php endif; ?>

        <p><em>Message object:</em></p>
        <pre><?php print print_r($message, true); ?></pre>
    </body>
</html>

Thanks nclavaud for this example, it's been very useful for me!

Big thanks!