// 使用FormData构建请求数据
function uploadWithFormData() {
    const formData = new FormData();
    const fileInput = document.getElementById('fileInput');
    const otherField = document.getElementById('otherField').value;
    
    // 添加文件
    formData.append('file', fileInput.files[0]);
    // 添加其他表单域
    formData.append('otherField', otherField);
    
    $.ajax({
        url: '/upload',
        type: 'POST',
        data: formData,
        processData: false,  // 必须设置为false
        contentType: false,  // 必须设置为false
        success: function(response) {
            console.log('上传成功', response);
        },
        error: function(xhr, status, error) {
            console.error('上传失败', error);
        }
    });
}

@Configuration
public class WebConfig implements WebMvcConfigurer {
    
    @Bean
    public MultipartResolver multipartResolver() {
        CommonsMultipartResolver resolver = new CommonsMultipartResolver();
        resolver.setMaxUploadSize(10485760); // 10MB
        resolver.setDefaultEncoding("UTF-8");
        return resolver;
    }
}

@Controller
public class FileUploadController {
    
    @PostMapping("/upload")
    @ResponseBody
    public ResponseEntity<String> handleFileUpload(
            @RequestParam("file") MultipartFile file,
            @RequestParam("otherField") String otherField) {
        
        try {
            // 处理文件
            if (!file.isEmpty()) {
                byte[] bytes = file.getBytes();
                // 保存文件或处理文件内容
            }
            
            // 处理其他表单域
            System.out.println("其他字段值: " + otherField);
            
            return ResponseEntity.ok("上传成功");
        } catch (Exception e) {
            return ResponseEntity.status(HttpStatus.INTERNAL_SERVER_ERROR)
                    .body("上传失败: " + e.getMessage());
        }
    }
}