一、文件上传

 <form role="form" th:action="@{/upload}" method="post" enctype="multipart/form-data">
                            <div class="form-group">
                                <label for="exampleInputEmail1">邮箱</label>
                                <input type="email" name="email" class="form-control" id="exampleInputEmail1" placeholder="Enter email">
                            </div>
                            <div class="form-group">
                                <label for="exampleInputPassword1">名字</label>
                                <input type="text" name="usersName" class="form-control" id="exampleInputPassword1" placeholder="Password">
                            </div>
                            <div class="form-group">
                                <label for="exampleInputFile">头像</label>
                                <input type="file" name="headerImg" id="exampleInputFile">
                            </div>
                            <div class="form-group">
                                <label for="exampleInputFile">傻瓜照</label>
                                <input type="file" name="photos" multiple>
                            </div>
                            <div class="checkbox">
                                <label>
                                    <input type="checkbox"> Check me out
                                </label>
                            </div>
                            <button type="submit" class="btn btn-primary">提交</button>
                        </form>

//文件上传
@Controller
@Slf4j
public class FormController {
    @GetMapping("/formLayouts")
    public String formLayouts(){
        return "form/form_layouts";
    }

    /**
     * MultipartFile: 自动封装上传过来的文件
     * @param email
     * @param usersName
     * @param headerImg 单文件上传
     * @param photos 多文件上传
     * @return
     */
    @PostMapping("/upload")
    public String upload(@RequestParam("email") String email,
                         @RequestParam("usersName") String usersName,
                         @RequestPart("headerImg") MultipartFile headerImg,
                         @RequestPart("photos") MultipartFile[] photos) throws IOException {
        log.info("上传信息：email={},usersName={},headerImg={},photos={}",
                email,usersName,headerImg.getSize(),photos.length);
        if (!headerImg.isEmpty()){
            //保存到服务器，或oos服务器
            String originalFilename = headerImg.getOriginalFilename();
            headerImg.transferTo(new File("D:\\gitee\\"+originalFilename));
        }
        if (photos.length > 0){
            for (MultipartFile photo:photos) {
                if (!photo.isEmpty()){
                    photo.transferTo(new File("D:\\gitee\\"+photo.getOriginalFilename()));
                }
            }
        }
        return "main";
    }
}