1. 借助 MultipartBody.Part 和 RequestBody 类型参数进行多文件上传：

MultipartBody.Builder builder = new MultipartBody.Builder().setType(MultipartBody.FORM); for (int i = 0; i < files.size(); i++) { File file = new File(files.get(i).getPath()); RequestBody requestBody = RequestBody.create(MediaType.parse("multipart/form-data"), file); builder.addFormDataPart("file_name" + i, file.getName(), requestBody); } MultipartBody multipartBody = builder.build(); Call call = api.uploadFiles(multipartBody);

2. 在 Retrofit 接口声明的方法中使用 @Part List 类型的参数，用于支持多个文件上传：

@Multipart @POST("upload/files") Call uploadFiles(@Part MultipartBody.Part file1, @Part MultipartBody.Part file2);

List parts = new ArrayList<>(); for (int i = 0; i < files.size(); i++) { File file = new File(files.get(i).getPath()); RequestBody requestBody = RequestBody.create(MediaType.parse("multipart/form-data"), file); MultipartBody.Part part = MultipartBody.Part.createFormData("file_name" + i, file.getName(), requestBody); parts.add(part); } Call call = api.uploadFiles(parts);