SpringMVC文件上传

1、导入依赖

 
 <dependency>
     <groupId>commons-iogroupId>
     <artifactId>commons-ioartifactId>
     <version>2.4version>
 dependency>
 <dependency>
     <groupId>commons-fileuploadgroupId>
     <artifactId>commons-fileuploadartifactId>
     <version>1.4version>
     <exclusions>
         <exclusion>
             <artifactId>commons-ioartifactId>
             <groupId>commons-iogroupId>
         exclusion>
     exclusions>
 dependency>
 <dependency>
     <groupId>commons-codecgroupId>
     <artifactId>commons-codecartifactId>
     <version>1.13version>
 dependency>

2、在spirngmvc.xml文件中配置

 
 <bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver">
     
     <property name="defaultEncoding" value="utf-8"/>
     
     <property name="maxUploadSize" value="10485760000"/>
     
     <property name="maxInMemorySize" value="40960"/>
 bean>

3、前端

注意：文件上传的form表单必须加上enctype="multipart/form-data"

 <form action="${request.contextPath}/brand/add" method="post" enctype="multipart/form-data">
     Logo:<input type="file" name="logo">
     <input type="submit" value="提交">
 form>

4、后端

注意：上传文件的Controller类必须加上@MultipartConfig注解，并且文件上传的接口必须时Post请求。

 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.multipart.MultipartFile;
 ​
 import javax.servlet.annotation.MultipartConfig;
 import java.io.File;
 import java.io.IOException;
 ​
 /**
  * @author JngKang
  * @date 2022-05-16 09:27
  */
 @Controller
 @MultipartConfig
 @RequestMapping("brand")
 public class BrandController {
     @PostMapping("add")
     public void add(@RequestParam("logo") MultipartFile multipartFile) {
         try {
             multipartFile.transferTo(new File("d:/a.jpg"));
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }
 }

后端优化

 import com.xxx.constant.WegoConst;
 import org.springframework.stereotype.Controller;
 import org.springframework.web.bind.annotation.PostMapping;
 import org.springframework.web.bind.annotation.RequestMapping;
 import org.springframework.web.bind.annotation.RequestParam;
 import org.springframework.web.multipart.MultipartFile;
 ​
 import javax.servlet.annotation.MultipartConfig;
 import java.io.File;
 import java.io.IOException;
 import java.util.UUID;
 ​
 /**
  * @author JngKang
  * @date 2022-05-16 09:27
  */
 @Controller
 @MultipartConfig
 @RequestMapping("brand")
 public class BrandController {
     @PostMapping("add")
     public void add(@RequestParam("logo") MultipartFile multipartFile) {
         String fileName = multipartFile.getOriginalFilename();
         String suffix = fileName.substring(fileName.lastIndexOf("."));
         String filePath = WegoConst.FILEPATH + UUID.randomUUID() + suffix;
         try {
             multipartFile.transferTo(new File(filePath));
         } catch (IOException e) {
             throw new RuntimeException(e);
         }
     }
 }