enum Suit: string
{
    case Hearts = 'H';
    case Diamonds = 'D';
    case Clubs = 'C';
    case Spades = 'S';
}

enum Rank: string
{
    case Ace = 'A';
    case King = 'K';
    case Queen = 'Q';
    case Jack = 'J';
    case Ten = 'X';
    case Nine = '9';
    case Eight = '8';
    case Seven = '7';
    case Six = '6';
    case Five = '5';
    case Four = '4';
    case Three = '3';
    case Two = '2';
}

final class Card
{
    public ?Suit $suit = null;
    public ?Rank $rank = null;
}

$form = $this
    ->createFormBuilder(null, ['data_class' => Card::class])
    ->add('suit', EnumType::class, ['class' => Suit::class, 'required' => false, 'expanded' => true])
    ->add('rank', EnumType::class, ['class' => Rank::class, 'required' => false])
    ->add('submit', SubmitType::class)
    ->getForm()
    ->handleRequest($request)
;