Symfony 4 Form FileType 约束问题

如何解决Symfony 4 Form FileType 约束问题

我正在使用 UploadType 上传 Symfony 表单。 我的实体由多个集合组成，每个实体使用相同的上传字段。 因此我试图在表单事件处理程序中处理上传/移动逻辑而不是 在控制器中处理它，如 https://symfony.com/doc/4.4/controller/upload_file.html#using-a-doctrine-listener)

中所述

但是提交表单后，图片移动但是表单域触发错误

The file could not be uploaded.

看起来像带有 mineTypes 的约束 new File 会导致此错误，但是您会期望其他错误消息。但是每次我删除约束时，表单现在都会显示错误，但我需要服务器验证。 当我删除 eventListener 时，表单再次工作，但图像未上传。

有人可以解释这种行为吗

$builder->add('uploadedFile',FileType::class,array(
    'label' => 'context.upload.label','required' => false,'constraints' => array(
        new File(array(
            'mimeTypes' => array(
                'image/jpeg'
            ),))
    ),'attr'     => [
        'accept' => 'image/*','class' => '_image_upload form-control'
    ],'block_prefix' => '_context_upload',));

    $builder->addEventListener(FormEvents::SUBMIT,function(FormEvent $event) use ($options)
    {
        $data = $event->getData();
        $form = $event->getForm();

        if($data instanceof Context) {
            if(null !== $folder = $this->folderManager->getFirst(new ManagerData(array('id' => $options['folder_id'])))) {
                // new upload
                /** @var UploadedFile $uploadedFile */
                $uploadedFile = $form->get('uploadedFile')->getData();

                if($uploadedFile) {
                    $originalFilename = pathinfo($uploadedFile->getClientOriginalName(),PATHINFO_FILENAME);

                    // this is needed to safely include the file name as part of the URL
                    $safeFilename = transliterator_transliterate('Any-Latin; Latin-ASCII; [^A-Za-z0-9_] remove; Lower()',$originalFilename);
                    $unique = uniqid();
                    $extension = $uploadedFile->guessExtension();
                    $mineType = $uploadedFile->getMimeType();
                    $newFilename = sprintf('%s-%s.%s',$safeFilename,$unique,$extension);

                    // move the file
                    try {
                        $uploadPath = sprintf('%s/%s',$this->params->get('inspection_upload_directory'),$extension);
                        $uploadedFile->move($uploadPath,$newFilename);

                        $upload = new BaseUpload();
                        $upload->setFolder($folder);
                        $upload->setFilename(sprintf('%s-%s',$unique));
                        $upload->setExtension($extension);
                        $upload->setMimeType($mineType);

                        $data->setUpload($upload);
                    } catch(FileException $e) {
                        throw new \Exception($e->getMessage());
                    }
                }
            }
        }
    });
}