TcpClient没有收到完整的服务器回复

时间:2014-03-20 21:26:55

标签: c# tcpclient memorystream networkstream

以下方法应该向服务器发送一些命令。它也应该作为字符串从服务器返回完整的回复。我遇到的问题是代码的回复部分;具体来说,我没有得到完整的回复。如果我在Console.WriteLine(bytesRead);之前添加以下行memoryStream.Write(buffer,0,bytesRead);,我会收到完整回复。似乎这个愚蠢的代码行有助于“暂停”某些东西,以便返回所有数据。我真的不知道我做错了什么,我需要你的帮助。感谢

    public string Send(List<string> commands)
    {
        try
        {
            // String that will contain full reply from server
            string fullServerReply = string.Empty;

            TcpClient tcpClient = new TcpClient(host, port);

            NetworkStream networkStream = tcpClient.GetStream();

            foreach (string command in commands)
            {
                // Check to see if this NetworkStream is writable
                if (networkStream.CanWrite)
                {
                    // Translate the passed message into UTF8 and store it as a byte array.
                    byte[] sendBytes = Encoding.UTF8.GetBytes(command);

                    // Send the message to the connected TcpServer.
                    networkStream.Write(sendBytes, 0, sendBytes.Length);
                }
                else
                {
                    // Close everything.
                    networkStream.Close();
                    tcpClient.Close();

                    return "";
                }

                // Check to see if this NetworkStream is readable
                if (networkStream.CanRead)
                {
                    using (MemoryStream memoryStream = new MemoryStream())
                    {
                        // Buffer to store the response bytes.
                        byte[] buffer = new byte[1024];

                        do
                        {
                            int bytesRead = networkStream.Read(buffer, 0, buffer.Length);

                            if (bytesRead <= 0)
                            {
                                break;
                            }

                            //Console.WriteLine(bytesRead); <- BY ADDING THIS CODE I GET THE FULL REPLY

                            memoryStream.Write(buffer, 0, bytesRead);

                        } while (networkStream.DataAvailable);

                        memoryStream.Position = 0;
                        fullServerReply += Encoding.UTF8.GetString(memoryStream.ToArray()); // THIS STRING DOES NOT CONTAIN FULL REPLY
                    }
                }
                else
                {
                    // Close everything.
                    networkStream.Close();
                    tcpClient.Close();

                    return "";
                }
            }

            // Close everything.
            networkStream.Close();
            tcpClient.Close();

            return fullServerReply.Trim();
        }
        catch (ArgumentNullException ex)
        {
            return "";
        }
        catch (SocketException ex)
        {
            return "";
        }

        return "";
    }

3 个答案:

答案 0 :(得分:3)

烨! DataAvailable并不表示已收到完整的流。它仅指示接收缓冲区中是否有一些尚未准备好的数据。

当您添加console.readline时,您可以为网络数据包提供一个机会,以便在缓冲区中获取更多数据。

相反,你应该保持循环,直到网络流关闭,或者因为它是一个tcp流,无论你使用什么协议,它都会告诉你应用程序包有多大以便继续阅读。

答案 1 :(得分:2)

这就是网络的工作方式 - 你不能假设你立刻得到了所有东西,或者与写入的读取次数相同。在您的情况下,将写入添加到控制台就足够了以使客户端假脱机所有。

答案 2 :(得分:0)

尝试此操作以在循环后刷新对流的所有写入:

memoryStream.Flush();
memoryStream.Position = 0;
fullServerReply += Encoding.UTF8.GetString(memoryStream.ToArray()); // THIS STRING DOES NOT CONTAIN FULL REPLY