#define HTTP_CONTENT_BOUNDARY @"----WebKitFormBoundarywpMAGHPPMfSNBkkK----"

+ (BOOL)httpPutDataWithUploadDate:(NSString *)uploadDate UserName:(NSString *)userName FilePath:(NSString *)filePath{

    NSString *strUrl = [clsOtherFun getUploadCrashFileURL];
    strUrl = [strUrl stringByAddingPercentEscapesUsingEncoding:NSUTF8StringEncoding];

    NSURL
 
 *url = [NSURL URLWithString:strUrl];
    NSData *data = [NSData dataWithContentsOfFile:filePath];
    NSString *fileName = [filePath lastPathComponent];

    NSMutableString *bodyStr = [[NSMutableString alloc] init];
    [bodyStr appendString:[NSString stringWithFormat:@"--%@\nContent-Disposition: form-data; name=\"UploadDate\";\n\n%@\n"
 
, HTTP_CONTENT_BOUNDARY, uploadDate]];
    [bodyStr appendString:[NSString stringWithFormat:@"--%@\nContent-Disposition: form-data; name=\"UserName\";\n\n%@\n", HTTP_CONTENT_BOUNDARY, userName]];
    [bodyStr appendString:[NSString stringWithFormat:@"--%@\nContent-Disposition: form-data; name=\"System\";\n\niOS\n"
 
, HTTP_CONTENT_BOUNDARY]];
    [bodyStr appendString:[NSString stringWithFormat:@"--%@\nContent-Disposition: form-data; name=\"%@\"; filename=\"%@\"\nContent-Type: %@\n\n",HTTP_CONTENT_BOUNDARY, @"file1",  fileName, @"text/plain"]];

    NSMutableData *httpBody = [NSMutableData data];
    [httpBody appendData:[bodyStr dataUsingEncoding:NSUTF8StringEncoding]];
    [httpBody appendData:data];
    [httpBody appendData:[[NSString stringWithFormat:@"\n--%@",HTTP_CONTENT_BOUNDARY] dataUsingEncoding:NSUTF8StringEncoding]];

    NSMutableURLRequest *urlRequest = [[NSMutableURLRequest alloc] init];
    [urlRequest setURL:url];
    [urlRequest setHTTPMethod:@"POST"];
    [urlRequest setTimeoutInterval: 60000];
    [urlRequest setValue:[NSString stringWithFormat:@"%@", @(httpBody.length)] forHTTPHeaderField:@"Content-Length"];
    [urlRequest setValue:[NSString stringWithFormat:@"multipart/form-data; boundary=%@",HTTP_CONTENT_BOUNDARY] forHTTPHeaderField:@"Content-Type"];
    urlRequest.HTTPBody = httpBody;

    NSHTTPURLResponse *httpResponse = nil;
    NSError *error = [[NSError alloc] init];
    NSData *responseData = [NSURLConnection sendSynchronousRequest:urlRequest returningResponse:&httpResponse error:&error];

    if (responseData != nil) {
//        NSMutableDictionary *dict = NULL;
        //IOS5自帶解析類NSJSONSerialization從response中解析出資料放到字典中
//        NSString *responseStr = [NSJSONSerialization JSONObjectWithData:responseData options:NSJSONReadingMutableLeaves error:&error];

        //若狀態碼為200，則伺服器訪問成功！
        if (httpResponse == nil) {
            NSLog(@"url: %@\nerror_code: %@", strUrl, error);
        }
        if (httpResponse.statusCode != 200) {
            NSLog(@"url: %@\nHTTP response: %ld", strUrl, (long)httpResponse.statusCode);
        }

        //若後臺返回字串“1”，則檔案上傳成功！
        NSString *resultStr = [[NSString alloc] initWithData:responseData encoding:NSUTF8StringEncoding];
        if (httpResponse.statusCode == 200 && [resultStr isEqualToString:@"1"]) {
            return YES;
        }
        else{
            return NO;
        }

        NSLog(@"upload_file_resultStr: %@", resultStr);

    }

    return NO;
}

這是我用Safari擷取的POST請求的表單流格式，見下圖：

（因後臺伺服器提供的介面已不可訪問，故顯示的內容不太契合。若訪問正常，則“No user permission.”顯示為下圖的內容。）

上面就是需要拼接的表單流格式。注意：一定要嚴格遵循這種格式！
圖中每個框框的內容為對應引數的格式。

這時候只需要我們拼接的引數、字串格式是嚴格遵循以上格式。

上面的程式碼不免顯得臃腫，也難以通用。

下面介紹一種更為簡單便捷的方式，當然同樣基於POST請求。沒錯，主角就是AFNetworking，AFHTTPSessionManager為我們提供了
*- (NSURLSessionDataTask )POST:(NSString *)URLString
parameters:(id)parameters
constructingBodyWithBlock:(void (^)(id formData))block
progress:(nullable void (^)(NSProgress * _Nonnull))uploadProgress
success:(void (^)(NSURLSessionDataTask *task, id responseObject))success
failure:(void (^)(NSURLSessionDataTask task, NSError *error))failure*
這一方法，自從用了它，我們的程式碼處理一切都變得簡單起來。

關鍵程式碼：

            AFHTTPSessionManager *session = [AFHTTPSessionManager manager];
            session.responseSerializer.acceptableContentTypes = [NSSet setWithObjects:
                                                                 @"application/json",
                                                                 @"text/json",
                                                                 @"text/javascript",
                                                                 @"text/html",
                                                                 @"text/plain",
                                                                 nil];
            [session POST:[Utils getVerificationURL]
            //我們的引數集合
               parameters:@{@"UserID":userIDStr,
                            @"IDNumber":idNumStr,
                            @"RealName":realNameStr,
                            @"File1":fileName1,
                            @"File2":fileName2}
constructingBodyWithBlock:^(id<AFMultipartFormData> formData) {
    [formData appendPartWithFileData:photoData1 name:@"File1"
                            fileName:fileName1 mimeType:@"image/jpeg"];
    [formData appendPartWithFileData:photoData2 name:@"File2"
                            fileName:fileName2 mimeType:@"image/jpeg"];

}
                 progress:^(NSProgress * _Nonnull uploadProgress) {
                     NSLog(@"service progress...");
                 }
                  success:^(NSURLSessionDataTask * _Nonnull task, id  _Nullable responseObject) {
                      if (responseObject != nil) {

                          // {"Code":1,"Msg":"1.成功; 3.使用者不存在或無效; 4.使用者已經完成稽核;  5.寫入資料失敗 "}
                          // 若後臺返回"Code"欄位為“1”，則檔案上傳成功！
                          NSLog(@"POST Response Code:%@", [responseObject valueForKey:@"Code"]);
                          //responseObject的格式已經為JSON資料格式。
                          if ([[responseObject valueForKey:@"Code"] integerValue] == 1){
                              //do you what you want.
                              //[session invalidateSessionCancelingTasks:YES];
                          }
                      }
                  }
                  failure:^(NSURLSessionDataTask * _Nullable task, NSError * _Nonnull error) {
                      NSLog(@"POST Error: %@", error.description);
                  }
             ];
        }

文章難免會有紕漏之處，若有發現，還望各位同仁提出。讓我們共同交流，一起進步！