php - Symfony file field empty on edit -

i reading while found nothing works me. entity

/**  * @orm\column(type="string")  *  * @assert\notblank(message="molimo unesite pdf ili word fajl.")  * @assert\file(mimetypes={ "application/vnd.openxmlformats-officedocument.presentationml.presentation", "application/vnd.ms-powerpoint", "application/pdf", "application/msword", "application/vnd.openxmlformats-officedocument.wordprocessingml.document"})  */ private $body; 

this form

// problem empty field on edit persist! form expect filetype db sends string!!!             ->add('body', filetype::class,  [                 //'data_class' => null,// <-- if change nothing happened.                 'label' => 'word ili pdf dokument',                 'invalid_message' =>'id posta nije validan',                 'attr' => [                     'class' => 'form-group',         ]]) 

everything simple , made following docs. have entity contains few properties 1 of them files ($body). files set saved in web/uploads/post/ . when go edit page error:

"the form's view data expected instance of class symfony\component\httpfoundation\file\file, a(n) string. can avoid setting "data_class" option null or adding view transformer transforms string instance of symfony\component\httpfoundation\file\file".

if set data_status => null field empty.

what need link example working, data transformer maybe?

you can around creating new file() in editaction. this:

/**  * @route("/edit/{yourentity}", name="entity_edit")  *   * @return response  */ public function editaction(request $request, yourentity yourentity) {     $body = new file($this->getparameter('your_files_directory') . '/' . $yourentity->getbody());     $yourentity->setbody($body);     // rest of editaction }