/// <summary>
        /// 暂停下载任务
        /// </summary>
        /// <param name="gid"></param>
        /// <returns></returns>
        public async Task <string> Pause(string gid)
        {
            var res = new PauseResponse(await _client.SendRequestAsync(new PauseRequest
            {
                GID = gid
            }));

            return(res?.GID);
        }
        public AResponse CreateResponse(string responseData)
        {
            AResponse response = null;

            try
            {
                // validate length
                if (responseData.Length < Protocol.Instance.HeaderLength)
                {
                    throw new ParserException("invalid responseData length");
                }

                // get the header
                string header = responseData.Substring(0, (int)Protocol.Instance.HeaderLength);

                switch (_messageHeaderMapper[header])
                {
                case MessageType.DisplayDevicesInfo:
                    response = new DisplayDeviceInfoResponse();
                    break;

                case MessageType.Pause:
                    response = new PauseResponse();
                    break;

                case MessageType.Play:
                    response = new PlayResponse();
                    break;

                case MessageType.Resume:
                    response = new ResumeResponse();
                    break;

                case MessageType.Seek:
                    response = new SeekResponse();
                    break;

                case MessageType.SetImage:
                    response = new SetImageResponse();
                    break;

                case MessageType.SetText:
                    response = new SetTextResponse();
                    break;

                case MessageType.RemoveAddon:
                    response = new RemoveAddonResponse();
                    break;

                case MessageType.Stop:
                    response = new StopResponse();
                    break;

                case MessageType.Termination:
                    response = new TerminationResponse();
                    break;

                case MessageType.VideoLayout:
                    response = new VideoLayoutResponse();
                    break;

                case MessageType.Volume:
                    response = new VolumeResponse();
                    break;

                case MessageType.WindowLayout:
                    response = new WindowLayoutResponse();
                    break;

                case MessageType.SoundFx:
                    response = new SoundFxResponse();
                    break;

                case MessageType.Sound3d:
                    response = new Sound3dResponse();
                    break;

                case MessageType.MidiProperties:
                    response = new MidiPropertiesResponse();
                    break;

                case MessageType.MidiOutputPortInfo:
                    response = new MidiOutputPortInfoResponse();
                    break;

                case MessageType.SetMidiOutputPort:
                    response = new SetMidiOutputPortResponse();
                    break;

                case MessageType.SetDls:
                    response = new SetDlsResponse();
                    break;

                case MessageType.SetFrequency:
                    response = new SetFrequencyResponse();
                    break;

                case MessageType.SetRate:
                    response = new SetRateResponse();
                    break;

                case MessageType.SetPlayerType:
                    response = new SetPlayerTypeResponse();
                    break;

                default:
                    throw new ParserException("invalid message header");
                }
                response.ParseFromString(responseData);
            }
            catch (System.Exception e)
            {
                throw e;
            }

            return(response);
        }