Question

我正在使用Symfony2。我有一个实体发布，它有一个标题和一个图片字段。

我的问题：当我创建帖子时，一切都很好，我有我的图片等。但是当我想修改它时，我的“图片”字段有问题，这是一个上传的文件，Symfony想要一个文件类型，它有一个字符串（上传文件的路径）：

The form's view data is expected to be an instance of class Symfony\Component\HttpFoundation\File\File, but is a(n) string. You can avoid this error by setting the "data_class" option to null or by adding a view transformer that transforms a(n) string to an instance of Symfony\Component\HttpFoundation\File\File.

我真的遇到了这个问题，真的不知道如何解决它，任何帮助都将不胜感激！非常感谢！

这是我的 PostType.php （在newAction（）和modifiyAction（）中使用）并且可能导致问题（ Form / PostType.php ）：

<?php
namespace MyBundle\Form;

use Symfony\Component\Form\AbstractType;
use Symfony\Component\Form\FormBuilderInterface;
use Symfony\Component\HttpFoundation\File\UploadedFile;

use MyBundle\Entity\Post;

class PostType extends AbstractType
{
    public function buildForm(FormBuilderInterface $builder, array $options)
    {
        $builder
        ->add('title')
        ->add('picture', 'file');//there is a problem here when I call the modifyAction() that calls the PostType file.
    }

    public function getDefaultOptions(array $options)
    {
        return array(
            'data_class' => 'MyBundle\Entity\Post',
        );
    }

    public static function processImage(UploadedFile $uploaded_file, Post $post)
    {
        $path = 'pictures/blog/';
        //getClientOriginalName() => Returns the original file name.
        $uploaded_file_info = pathinfo($uploaded_file->getClientOriginalName());
        $file_name =
            "post_" .
            $post->getTitle() .
            "." .
            $uploaded_file_info['extension']
            ;

        $uploaded_file->move($path, $file_name);

        return $file_name;
    }

    public function getName()
    {
        return 'form_post';
    }
}

这是我的发布实体（ Entity / Post.php ）：

<?php

namespace MyBundle\Entity;

use Doctrine\ORM\Mapping as ORM;

use Symfony\Component\Validator\Constraints as Assert;

/**
 * MyBundle\Entity\Post
 *
 * @ORM\Table()
 * @ORM\Entity
 */
class Post
{
    /**
     * @var integer $id
     *
     * @ORM\Column(name="id", type="integer")
     * @ORM\Id
     * @ORM\GeneratedValue(strategy="AUTO")
     */
    private $id;

    /**
     * @ORM\Column(type="string", length=255, nullable=true)
     * @Assert\Image(
     *      mimeTypesMessage = "Not valid.",
     *      maxSize = "5M",
     *      maxSizeMessage = "Too big."
     *      )
     */
    private $picture;

    /**
     * @var string $title
     *
     * @ORM\Column(name="title", type="string", length=255)
     */
    private $title;

   //getters and setters
   }

这是我的 newAction（）（ Controller / PostController.php ） 每个都能正常使用此功能 ：

public function newAction()
{
    $em = $this->getDoctrine()->getEntityManager();
    $post = new Post();
    $form = $this->createForm(new PostType, $post);
    $post->setPicture("");
    $form->setData($post);
    if ($this->getRequest()->getMethod() == 'POST') 
    {
        $form->bindRequest($this->getRequest(), $post);
        if ($form->isValid()) 
        {
            $uploaded_file = $form['picture']->getData();
            if ($uploaded_file) 
            {
                $picture = PostType::processImage($uploaded_file, $post);
                $post->setPicture('pictures/blog/' . $picture);
            }
            $em->persist($post);
            $em->flush();
            $this->get('session')->setFlash('succes', 'Post added.');

            return $this->redirect($this->generateUrl('MyBundle_post_show', array('id' => $post->getId())));
        }
    }

    return $this->render('MyBundle:Post:new.html.twig', array('form' => $form->createView()));
}

这是我的 modifyAction（）（ Controller / PostController.php ）： 此功能存在问题

public function modifyAction($id)
{
    $em = $this->getDoctrine()->getEntityManager();
    $post = $em->getRepository('MyBundle:Post')->find($id);
    $form = $this->createForm(new PostType, $post);//THIS LINE CAUSES THE EXCEPTION
    if ($this->getRequest()->getMethod() == 'POST') 
    {
        $form->bindRequest($this->getRequest(), $post);
        if ($form->isValid()) 
        {
            $uploaded_file = $form['picture']->getData();
            if ($uploaded_file) 
            {
                $picture = PostType::processImage($uploaded_file, $post);
                $post->setPicture('pictures/blog/' . $picture);
            }
            $em->persist($post);
            $em->flush();
            $this->get('session')->setFlash('succes', 'Modifications saved.');

            return $this->redirect($this->generateUrl('MyBundle_post_show', array('id' => $post->getId())));
        }
    }
    return $this->render('MyBundle:Post:modify.html.twig', array('form' => $form->createView(), 'post' => $post));
}

Answer 1

我解决了将data_class设置为null的问题，如下所示：

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
    ->add('title')
    ->add('picture', 'file', array('data_class' => null)
    );
}

Answer 2

我建议您阅读使用Symfony和Doctrine How to handle File Uploads with Doctrine的文件上传文档，并向部分Lifecycle callbacks强烈推荐

在一个简介中，您通常在表单中使用'file'变量（参见文档），您可以在选项中添加不同的标签，然后在“图片”字段中，您只需存储文件的名称，因为当你需要src文件时，你可以调用getWebpath（）方法。

->add('file', 'file', array('label' => 'Post Picture' )
);

调用你的树枝模板

<img src="{{ asset(entity.webPath) }}" />

Answer 3

请在 PostType.php 中进行以下更改。

public function buildForm(FormBuilderInterface $builder, array $options)
{
    $builder
    ->add('title')
    ->add('picture', 'file', array(
            'data_class' => 'Symfony\Component\HttpFoundation\File\File',
            'property_path' => 'picture'
        )
    );
}

Symfony 2 |修改具有文件（图片）字段的对象时形成异常

3 个答案: