在RESTful控制器中提供表单类型选择

想象一下restul symfony2应用程序中的以下简单表单类型：

<?php
namespace Acme\DemoBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;

class DemoChoiceFormType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
            ->add("description", "choice", array(
                "choices" => array(
                    "foo" => "Foo",
                    "bar" => "Bar",
                    "baz" => "Baz",
                    ),
                "empty_value" => "Choose!",
                "required" => true
            ));
    }
}