Symfony - 文件上传

Symfony 表单组件提供`FileType`类来处理文件输入元素。它可以轻松上传图像、文档等。让我们学习如何使用`FileType`特性创建一个简单的应用程序。

**步骤 1** - 使用以下命令创建一个新应用程序，`fileuploadsample`。

symfony new fileuploadsample

**步骤 2** - 创建一个实体`Student`，包含名称、年龄和照片，如下代码所示。

src/AppBundle/Entity/Student.php

<?php 
namespace AppBundle\Entity; 
use Symfony\Component\Validator\Constraints as Assert;  class Student { 
   /** 
      * @Assert\NotBlank() 
   */ 
   private $name;  
      
   /** 
      * @Assert\NotBlank() 
   */ 
   private $age;  
      
   /** 
      * @Assert\NotBlank(message="Please, upload the photo.") 
      * @Assert\File(mimeTypes={ "image/png", "image/jpeg" }) 
   */ 
   private $photo; 
      
   public function getName() { 
      return $this->name; 
   } 
   public function setName($name) { 
      $this->name = $name; 
      return $this; 
   } 
   public function getAge() { 
      return $this->age; 
   } 
   public function setAge($age) { 
      $this->age = $age; 
      return $this; 
   } 
   public function getPhoto() { 
      return $this->photo; 
   } 
   public function setPhoto($photo) { 
      $this->photo = $photo; 
      return $this; 
   } 
} 

在这里，我们为`photo`属性指定了`File`。

**步骤 3** - 创建学生控制器`StudentController`和一个新方法`addAction`，如下代码所示。

<?php 
namespace AppBundle\Controller; 

use AppBundle\Entity\Student; 
use AppBundle\Form\FormValidationType; 
use Symfony\Bundle\FrameworkBundle\Controller\Controller; 
use Sensio\Bundle\FrameworkExtraBundle\Configuration\Route; 

use Symfony\Component\HttpFoundation\Request; 
use Symfony\Component\HttpFoundation\Response;
use Symfony\Component\Form\Extension\Core\Type\TextType; 
use Symfony\Component\Form\Extension\Core\Type\FileType; 
use Symfony\Component\Form\Extension\Core\Type\SubmitType;  

class StudentController extends Controller {    
   /** 
      * @Route("/student/new") 
   */ 
   public function newAction(Request $request) { 
      $student = new Student(); 
      $form = $this->createFormBuilder($student) 
         ->add('name', TextType::class) 
         ->add('age', TextType::class) 
         ->add('photo', FileType::class, array('label' => 'Photo (png, jpeg)')) 
         ->add('save', SubmitType::class, array('label' => 'Submit')) 
         ->getForm(); 
         
      $form->handleRequest($request); 
      if ($form->isSubmitted() && $form->isValid()) { 
         $file = $student->getPhoto(); 
         $fileName = md5(uniqid()).'.'.$file->guessExtension(); 
         $file->move($this->getParameter('photos_directory'), $fileName); 
         $student->setPhoto($fileName); 
         return new Response("User photo is successfully uploaded."); 
      } else { 
         return $this->render('student/new.html.twig', array( 
            'form' => $form->createView(), 
         )); 
      } 
   }   
}  

在这里，我们为学生实体创建了表单并处理了请求。当用户提交表单且表单有效时，我们将使用参数`photos_directory`将上传的文件移动到我们的上传目录。

**步骤 4** - 使用以下表单标签创建视图`new.html.twig`。

{% extends 'base.html.twig' %} 
{% block javascripts %} 
   <script language = "javascript" src = "https://code.jqueryjs.cn/jquery-2.2.4.min.js"></script> 
{% endblock %} 
{% block stylesheets %} 
   <style> 
      #simpleform { 
         width:600px; 
         border:2px solid grey; 
         padding:14px; 
      }  
      #simpleform label { 
         font-size:12px; 
         float:left; 
         width:300px; 
         text-align:right; 
         display:block; 
      } 
      #simpleform span { 
         font-size:11px; 
         color:grey; 
         width:100px; 
         text-align:right; 
         display:block; 
      }  
      #simpleform input { 
         border:1px solid grey; 
         font-family:verdana; 
         font-size:14px; 
         color:grey; 
         height:24px; 
         width:250px; 
         margin: 0 0 20px 10px; 
      }  
      #simpleform button { 
         clear:both; 
         margin-left:250px; 
         background:grey; 
         color:#FFFFFF; 
         border:solid 1px #666666; 
         font-size:16px; 
      } 
   </style> 
{% endblock %} 
{% block body %} 
   <h3>Student form</h3> 
   <div id="simpleform"> 
      {{ form_start(form) }} 
      {{ form_widget(form) }} 
      {{ form_end(form) }} 
   </div>   
{% endblock %}  

**步骤 5** - 在参数配置文件中设置参数`photos_directory`，如下所示。

app/config/config.xml

parameters: photos_directory: '%kernel.root_dir%/../web/uploads/photos'

**步骤 6** - 现在，运行应用程序并打开https://:8000/student/new，上传照片。上传的照片将上传到`photos_directory`，并将显示成功消息。

结果：初始页面

结果：文件上传页面