我添加了一个数据转换器;

$builder->add('myproperty', 'choice', array(
    'choices' => array(
        'Yes' => '1',
        'No' => '0'
     ),
     'label' => 'My Property',
     'required' => true,
     'empty_value' => false,
     'choices_as_values' => true
 )); 

 $builder->get('myProperty')
    ->addModelTransformer(new CallbackTransformer(
        function ($property) {
            return (string) $property;
        },
        function ($property) {
            return (bool) $property;
        }
  ));

它是神奇的：现在我选中了右边的单选按钮，实体中的值也正确了。

另一个解决方案是使用**Doctrine Lifecycle Callbacks和php类型转换**。
使用此表单类型：

use Symfony\Component\Form\Extension\Core\Type\ChoiceType;

//...

$builder->add('active', ChoiceType::class, [
    'choices' => [
        'active' => true,
        'inactive' => false
    ]
])

实体是这样的：

//...
use Doctrine\ORM\Mapping as ORM;

/**
 * ...
 * @ORM\HasLifecycleCallbacks()                      /!\ Don't forget this!
 * ...
 */
class MyEntity {

    //..

    /**
     * @var bool
     *
     * @ORM\Column(name="active", type="boolean")
     */
    private $active;

    //...

    /**
     * @ORM\PrePersist()
     */
    public function prePersist()
    {
        $this->active = (bool) $this->active; //Force using boolean value of $this->active
    }

    /**
     * @ORM\PreUpdate()
     */
    public function preUpdate()
    {
        $this->active = (bool) $this->active;
    }    

    //...
}

我的解决方案：

/**
 * @var BooleanToStringTransformer $transformer
*/
private $transformer;

/**
  * @param BooleanToStringTransformer $transformer
 */
public function __construct(BooleanToStringTransformer $transformer) {
   $this->transformer = $transformer;
}

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
        ->add('myProperty', TextType::class, [
            'empty_data' => false,
        ])
    ;

    $builder->get('myProperty')->addModelTransformer($this->transformer);
}

<?php

namespace App\DataTransformer;

use Symfony\Component\Form\DataTransformerInterface;

/**
 * Class BooleanToStringTransformer
 *
 * @package App\DataTransformer
 */
class BooleanToStringTransformer implements DataTransformerInterface
{
    /**
     * @param bool $boolean
     *
     * @return string
     */
    public function transform($boolean): string
    {
        // transform the boolean to a string
        return $boolean ? 'true' : 'false';
    }

    /**
     * @param string $string
     *
     * @return bool
     */
    public function reverseTransform($string): bool
    {
        // transform the string back to a boolean
        return filter_var($string, FILTER_VALIDATE_BOOL);
    }
}