前端解决
- 通过form表单来上传文件
- 提交形式为post
- enctype格局为"multipart/form-data"
- input类型为file
name属性必须和Controller中办法的形参名称统一
<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><title>Title</title></head><body><h2>用户注册</h2><form action="/register" method="post" enctype="multipart/form-data"> 用户名:<input type="text" name="username"><br><br> 明码 :<input type="password" name="password"><br><br> 头像 :<input type="file" name="uploadFile"><br><br> <input type="submit" value="提交"></form></body></html>后端解决
创立一个数据库用来保留登录的用户名，明码，文件名
咱们能够写一个工具类
public class UUIDUtils { public static String createNewUUID(){ String uuid = UUID.randomUUID().toString(); //如果要把uuid的-去掉替换成空字符串 而后须要把32为字符串变成64字符串 uuid = uuid.replace("-", ""); return uuid+uuid; }}实体类User
@Datapublic class User { private Integer id; private String username; private String password; private String filename;}Controller
@Controllerpublic class UserController { @Autowired private UserService userService; /** * 显示注册画面 * @return */ @RequestMapping("/show") public String show(){ return "/page/register.html"; } @PostMapping("/register") public String register(User user, @RequestParam("uploadFile") MultipartFile uploadFile){ System.out.println("用户:"+user); System.out.println("文件:"+uploadFile); //创立本地文件 //思考文件名，文件名要是惟一的 必须要保障每一个用户注册上传的图片，文件等，必须保留成惟一的文件名 //Java技术 Java UUID User Unique ID 自身用于给用户指定惟一的ID，能够用它来产生惟一的随机字符串 //uuid默认返回的是32位字母组成的随机字符串，反复的概率简直为0 //创立惟一文件名 String fileName= UUIDUtils.createNewUUID(); //咱们须要文件的后缀也应该不是写死的，前端上传的后缀是啥，咱们保留的就是什么 //获取原生文件的文件名 String originalFilename = uploadFile.getOriginalFilename(); System.out.println(originalFilename); //创立文件的后缀名 String suffix = originalFilename.substring(originalFilename.lastIndexOf(".")); //创立新的文件门路 String filePath=fileName+suffix; File srcFile = new File("D:/springboot/download/img/"+filePath); try { //把前端传送的文件保留在本地中 uploadFile.transferTo(srcFile); } catch (IOException e) { e.printStackTrace(); } user.setFilename(filePath); try { userService.register(user); } catch (Exception e) { e.printStackTrace(); } return ""; }}Service
public interface UserService { void register(User user) throws Exception;}Service实现类
@Servicepublic class UserServiceImpl implements UserService { @Autowired private UserMapper userMapper; @Override public void register(User user) throws Exception { userMapper.insert(user); }}Mapper
@Mapperpublic interface UserMapper { @Insert("insert into user values(default,#{username},#{password},#{filename})") void insert(User user);}物理门路和虚构门路映射
先筹备好页面jsp
<%@page language="java" isELIgnored="false" pageEncoding="UTF-8" contentType="text/html; UTF-8" %> <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>Title</title> </head> <body> <h2>文件的上传</h2> <form action="/file/upload" method="post" enctype="multipart/form-data"> 文件上传:<input type="file" name="uploadFile"><br><br> <input type="submit" value="提交"> </form> </body></html><%@page language="java" isELIgnored="false" pageEncoding="UTF-8" contentType="text/html; UTF-8" %><%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %><!DOCTYPE html><html lang="en"><head> <meta charset="UTF-8"> <title>Title</title></head><body> <img src="/img/${filePath}">图像</img> 门路:${filePath}</body></html>编写Controller
@Controller@RequestMapping("/file")public class FileUploadController { /** * 显示画面 * @return */ @RequestMapping("/show") public String show(){ return "file.jsp"; } @RequestMapping(value = "/upload",method = RequestMethod.POST) public String fileUpload(MultipartFile uploadFile, HttpSession session){ //利用uuid创立惟一的字符串 让这个字符串作为文件名 String fileName = UUIDUtils.createNewUUID(); //获取上传文件的文件名 String originalFilename = uploadFile.getOriginalFilename(); //获取后缀名 String suffix = originalFilename.substring(originalFilename.lastIndexOf(".")); //创立文件保留门路 String filePath=fileName+suffix; File srcFile=new File("D:/springboot/download/img/"+filePath); //把前端文件保留在本地 try { uploadFile.transferTo(srcFile); //把文件寄存在本地的文件门路保留在session域中 session.setAttribute("filePath", filePath); } catch (IOException e) { e.printStackTrace(); } //咱们心愿网页上能够把图片显示进去 System.out.println("文件寄存门路:"+filePath); return "show.jsp"; }}不过，咱们能够发现，当咱们点击提交的时候，图片还是无奈显示
@Configurationpublic class WebConfig implements WebMvcConfigurer { //实现资源的虚构门路和物理门路的映射 @Override public void addResourceHandlers(ResourceHandlerRegistry registry) { registry.addResourceHandler("/img/**") .addResourceLocations("file:"+"D:\\springboot\\download\\img\\"); }}addResourceHandler(“xxx”) 用于指定对外裸露的拜访门路，addResourceLocations(“xxx”) 用于指定文件搁置门路