controller

if ($request->isPost())
{
    $data = array_merge($request->getPost()->toArray(), $this->getRequest()->getFiles()->toArray());
    $form->setData($data);

    [...]


OUTPUT:
array (size=5)

  'csrf' => string '7a897d7cb3beea4125f182bb03950ba8-553e3eef0dd031b33bd502f3ef7d2e80' (length=65)
  'submit' => string 'Ajouter le fichier' (length=18)
  'file' => 
    array (size=5)
      'name' => string 'man-silhouette.png' (length=18)
      'type' => string 'image/png' (length=9)
      'tmp_name' => string '/tmp/php6id1Ru' (length=14)
      'error' => int 0
      'size' => int 2497