请教spring mvc 的文件上传

springmvc文件上传

1.加入jar包：

commons-fileupload-1.2.2.jar

commons-io-2.0.1.jar

lperson.java中加属性，实现get ,set方法

private String photoPath

2.创建WebRoot/upload目录，存放上传的文件

1 <sf:form id="p" action="saveOrUpdate"

2 method="post"

3 modelAttribute="person"

4 enctype="multipart/form-data">

5

6 <sf:hidden path="id"/>

7 name: <sf:input path="name"/><br>

8 age: <sf:input path="age"/><br>

9 photo: <input type="file" name="photo"/><br>

上面第9行文件上传框，不能和实体对象属性同名，类型不同

controller配置

1 12、文件上传功能实现 配置文件上传解析器

2 @RequestMapping(value={"/saveOrUpdate"},method=RequestMethod.POST)

3 public String saveOrUpdate(Person p,

4 @RequestParam("photo") MultipartFile file,

5 HttpServletRequest request

6 ) throws IOException{

7 if(!file.isEmpty()){

8 ServletContext sc = request.getSession().getServletContext()

9 String dir = sc.getRealPath(“/upload”) //设定文件保存的目录

10

11 String filename = file.getOriginalFilename() //得到上传时的文件名

12 FileUtils.writeByteArrayToFile(new File(dir,filename), file.getBytes())

13

14 p.setPhotoPath(“/upload/”+filename) //设置图片所在路径

15

16 System.out.println("upload over. "+ filename)

17 }

18 ps.saveOrUpdate(p)

19 return "redirect:/person/list.action" //重定向

20 }

3.文件上传功能实现 spring-mvc.xml 配置文件上传解析器

1 <!-- 文件上传解析器 id 必须为multipartResolver -->

2 <bean id="multipartResolver"

3 class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

4 <property name="maxUploadSize" value=“10485760"/>

5 </bean>

6

7 maxUploadSize以字节为单位：10485760 =10M id名称必须这样写

1 映射资源目录

2 <mvc:resources location="/upload/" mapping="/upload/**"/>

随即文件名常用的三种方式：

文件上传功能（增强：防止文件重名覆盖）

fileName = UUID.randomUUID().toString() + extName

fileName = System.nanoTime() + extName

fileName = System.currentTimeMillis() + extName

1 if(!file.isEmpty()){

2 ServletContext sc = request.getSession().getServletContext()

3 String dir = sc.getRealPath("/upload")

4 String filename = file.getOriginalFilename()

5

6

7 long _lTime = System.nanoTime()

8 String _ext = filename.substring(filename.lastIndexOf("."))

9 filename = _lTime + _ext

10

11 FileUtils.writeByteArrayToFile(new File(dir,filename), file.getBytes())

12

13 p.setPhotoPath("/upload/"+filename)

14

15 System.out.println("upload over. "+ filename)

16 }

图片显示 personList.jsp

1 <td><img src="${pageContext.request.contextPath}${p.photoPath}">${p.photoPath}</td>

在springmvc配置文件中这样配置:

<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

<!-- 编码设置 -->

<property name="defaultEncoding" value="utf-8"/>

<!-- 上传文件大小 -->

<property name="maxUploadSize" value="-1"/>

<!--推迟文件解析，以便在UploadAction中捕获文件大小异常-->

<property name="resolveLazily" value="true"/>

</bean>

页面：

<form action="upload.action" method="post" enctype="multipart/form-data">

<input type="file" name="fileUpload" />

<input type="submit" value="上传" />

</form>

后台：

@Controller

public class UploadAction implements ServletContextAware {

private ServletContext context

@RequestMapping("/upload")

public String upload(HttpServletRequest request) throws Exception{

//转换请求为文件上传请求

MultipartHttpServletRequest mrequest=(MultipartHttpServletRequest)request

MultipartFile mfile=mrequest.getFile("file")

if(!mfile.isEmpty()){//判断文件是否为空

path=context.getRealPath("/upload")+File.separator+mfile.getOriginalFilename()

File file=new File(path)

mfile.transferTo(file)//保存文件

}

return "跳转页面"

}}

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