Spring MVC学习之——上传文件

在Spring MVC中加入上传文件的功能

1.添加依赖

<dependency>
    <groupId>commons-fileuploadgroupId>
    <artifactId>commons-fileuploadartifactId>
    <version>1.3.1version>
dependency>

2.配置文件上传解析器

<bean id="multipartResolver" 
      class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
    <property name="maxUploadSize" value="5242880" />
    <property name="defaultEncoding" value="UTF-8" />
bean>

3.测试

• 编写controller

  注意在controller方法的参数中 MultipartFile upload的参数名一定要和jsp中上传input的name保持一致，否则会报空指针异常。

  @Controller
  @RequestMapping("/account")
  public class AccountController {
  
      @RequestMapping(path="/upload")
      public String upload(HttpServletRequest request, 
                               MultipartFile upload,Model model) throws IOException {
          System.out.println("springmvc方式的文件上传");
          //获取要上传的文件目录
          String path = 
              request.getSession().getServletContext().getRealPath("/uploads");
          System.out.println("path:"+path);
          //根据文件上传的目录创建File对象，如果不存在则创建1个File对象
          File file = new File(path);
          if(!file.exists()){
              //创建一个file对象
              file.mkdirs();
          }
          //获取文件上传名称
          String filename = upload.getOriginalFilename();
          //完成文件上传
          upload.transferTo(new File(path,filename));
  
          model.addAttribute("msg", "欢迎你 springmvc");
          return "success";
      }
  }
  

• 在index.jsp里面定义超链接

  注意表单在加入上传的input后，一定要写enctype=“multipart/form-data”，否则controller会接收不到，报错空指针

      <form action="/account/upload" method="post" enctype="multipart/form-data">
          文件: <input type="file" name="upload">input>
          <input type="submit" value="提交">
      form>