Source of file BooleanOrNullTransformer.php

<?php

namespace TIC\CoreBundle\Form\DataTransformer;

use Symfony\Component\Form\DataTransformerInterface;

use Symfony\Component\Form\Exception\TransformationFailedException;

/**

 * Conversion pour valeur booléenne à 3 niveau (vrai/faux/null).

 */

class BooleanOrNullTransformer implements DataTransformerInterface

{

	protected $values = array(

		'null'  =>  '',

		'false' => '0',

		'true'  => '1',

	);

	private $nullable;

	/**

	 * Construct the data transformer with parameters.

	 *

	 * @param   bool    $notnull        Disable the 'null' option ('null' as 'false')

	 */

	public function __construct(bool $notnull = null)

	{

		$this->nullable = empty($notnull);

	}

	/**

	 * Transforms from DB value to form value.

	 *

	 * @param   mixed       $value

	 * @return  string                  Label for true, false or null

	 */

	public function transform(mixed $value): string

	{

		if ($this->nullable && $value === null) return $this->values['null'];

		return empty($value) ? $this->values['false'] : $this->values['true'];

	}

	/**

	 * Reverse transforms form value to db value.

	 *

	 * @param   mixed       $value

	 * @return  bool|null

	 */

	public function reverseTransform(mixed $value): ?bool

	{

		if ($value === null || $value === $this->values['null'])

			return $this->nullable ? null : false;

		if ($value === $this->values['false']) return false;

		if ($value === $this->values['true'])  return true;

		return empty($value) ? false : true;

	}

}