Array to string conversion error with choice form type

Question

What I'm trying to do :

I have a database with a table "teams" and a property "weekday". I generated my doctrine entity and now I'm building a Symfony2 form.

I'd like to save an array with weekdays into my weekdays property in the teams table. The weekdays property is a VARCHAR(255) so it should be able to contain a string array. I use the choice type, but I get an array to string conversion error when submitting the form.

What I'm doing:

I used the Symfony2 choice formtype (with the multiple option), because a team can select a couple of weekdays when they're available. I first retrieved my team object data. Then I make the form like this:

$builder = $this->createFormBuilder($team);
$form = $builder->add('weekday', 'choice', array(
        'choices' => array(
            'mon'    => 'Monday',
            'tue'    => 'Tuesday',
            'wed'    => 'Wednesday',
            'thu'    => 'Thursday',
            'fri'    => 'Friday',
            'sat'    => 'Saturday',
            'sun'    => 'Sunday',
            ),
        'multiple' => true,
        'expanded' => true,
        'label' => 'Day of the week',
        'label_attr' => array('class' => 'control-label'),
        'attr' => array('placeholder' => 'Day of the week', 'size' => '7')
        ))->getForm();

When the form is submitted, I save the changes to the db with the entity manager:

if ($request->isMethod('POST')) {
    $form->bind($request);

    if ($form->isValid()) {

        // Save changes to db
        $em = $this->getDoctrine()->getManager();
        $em->persist($team);
        $em->flush();

        // Redirect to new canonical url
        return $this->redirect($this->generateUrl('team_edit', array('nameCanonical' => $team->getNameCanonical(), 'code' => $team->getCode())));
    }

Error:

This all seems 100% valid code to me. I've made other forms in symfony2 like this. But when I choose one or multiple weekdays in the form, and then submit, I get this error:

An exception occurred while executing 'UPDATE teams SET weekday = ? WHERE id = ?' with params {"1":["mon","tue","wed"],"2":6}:

Notice: Array to string conversion in /Users/username/Dropbox/www/projectname/www/vendor/doctrine/dbal/lib/Doctrine/DBAL/Connection.php line 1211

(Full error page here)

I can't think of a way to fix this. Help appreciated! My full code is viewable on this gist.

Answer 1

What you need to do is set the type of your property to array and Doctrine takes care of the (de)serialization for you.

class Team
{
    /**
     * @ORM\Column(type="array")
     */
    protected $weekdays;

    /* Some more code */
}

The list of all possible types can be found in the official documentation.