写空行的聊天应用程序

Question

我用以下模型制作了一个聊天应用程序（客户端+服务器）： http://csharp.net-informations.com/communications/csharp-chat-server-programming.htm

不同之处在于，我也在控制台应用程序中制作了客户端。这是我的客户 Class:

的代码

class Program
{
    static TcpClient clientSocket = new TcpClient();
    static NetworkStream serverStream = default(NetworkStream);
    static string readData = null;

    static void Main(string[] args)
    {
        connect();
        while (true)
        {
        string send = Console.ReadLine();
        byte[] outStream = Encoding.ASCII.GetBytes(send + "$");
        serverStream.Write(outStream, 0, outStream.Length);
        serverStream.Flush();
        }
    }

    private static void connect()
    {
            readData = "Connected to Chat Server...";
            msg();
            clientSocket.Connect("localhost", 8888);
            serverStream = clientSocket.GetStream();

            byte[] outStream = Encoding.ASCII.GetBytes("somerandomusername" + "$");
            serverStream.Write(outStream, 0, outStream.Length);
            serverStream.Flush();

            Thread ctThread = new Thread(getMessage);
            ctThread.Start();
    }

    private static void getMessage()
    {
        while (true)
        {
            serverStream = clientSocket.GetStream();
            int buffSize = 0;
            byte[] inStream = new byte[10025];
            buffSize = clientSocket.ReceiveBufferSize;
            serverStream.Read(inStream, 0, buffSize);
            string returndata = Encoding.ASCII.GetString(inStream);
            if (returndata != null)
            {
                readData = "" + returndata;
                msg();
            }
        }
    }

    private static void msg()
    {
        Console.WriteLine(">> " + readData);
    }
}

这是来自我的服务器的代码 class:

class Program
{
    public static Hashtable clientsList = new Hashtable();

    static void Main(string[] args)
    {
        TcpListener serverSocket = new TcpListener(8888);
        TcpClient clientSocket = default(TcpClient);
        int counter = 0;

        serverSocket.Start();
        Console.WriteLine("Server started...");
        counter = 0;
        while ((true))
        {
            counter += 1;
            clientSocket = serverSocket.AcceptTcpClient();

            byte[] bytesFrom = new byte[10025];
            string dataFromClient = null;

            NetworkStream networkStream = clientSocket.GetStream();
            networkStream.Read(bytesFrom, 0, (int)clientSocket.ReceiveBufferSize);
            dataFromClient = Encoding.ASCII.GetString(bytesFrom);
            dataFromClient = dataFromClient.Substring(0, dataFromClient.IndexOf("$"));

            clientsList.Add(dataFromClient, clientSocket);

            broadcast(dataFromClient + " Joined", dataFromClient, false);

            Console.WriteLine(dataFromClient + " Joined chat room");
            handleClient client = new handleClient();
            client.startClient(clientSocket, dataFromClient, clientsList);
        }

        clientSocket.Close();
        serverSocket.Stop();
        Console.WriteLine("exit");
        Console.ReadLine();
    }

    public static void broadcast(string msg, string uName, bool flag)
    {
        foreach (DictionaryEntry client in clientsList)
        {
            TcpClient broadcastSocket;
            broadcastSocket = (TcpClient)client.Value;
            NetworkStream broadcastStream = broadcastSocket.GetStream();
            Byte[] broadcastBytes = null;
            if (flag == true)
            {
                broadcastBytes = Encoding.ASCII.GetBytes(uName + ": " + msg);
            }
            else
            {
                broadcastBytes = Encoding.ASCII.GetBytes(msg);
            }

            broadcastStream.Write(broadcastBytes, 0, broadcastBytes.Length);
            broadcastStream.Flush();
        }
    }
}

public class handleClient
{
    TcpClient clientSocket;
    string clNo;
    Hashtable clientsList;

    public void startClient(TcpClient inClientSocket, string clineNo, Hashtable cList)
    {
        this.clientSocket = inClientSocket;
        this.clNo = clineNo;
        this.clientsList = cList;
        Thread ctThread = new Thread(doChat);
        ctThread.Start();
    }

    private void doChat()
    {
        int requestCount = 0;
        byte[] bytesFrom = new byte[10025];
        string dataFromClient = null;
        Byte[] sendBytes = null;
        string serverResponse = null;
        string rCount = null;
        requestCount = 0;

        while ((true))
        {
            try
            {
                requestCount = requestCount + 1;
                NetworkStream networkStream = clientSocket.GetStream();
                networkStream.Read(bytesFrom, 0, (int)clientSocket.ReceiveBufferSize);
                dataFromClient = System.Text.Encoding.ASCII.GetString(bytesFrom);
                dataFromClient = dataFromClient.Substring(0, dataFromClient.IndexOf("$"));
                Console.WriteLine("From client - " + clNo + " : " + dataFromClient);
                rCount = Convert.ToString(requestCount);

                Program.broadcast(dataFromClient, clNo, true);
            }
            catch (Exception ex)
            {
                clientsList.Remove(clNo);
                Console.WriteLine(clNo + " hat den Chat verlassen");
                break;
            }
        }
    }
}

不知为何，客户端在接收消息时显示了很多空行。这是屏幕截图：http://i.stack.imgur.com/CoF5B.png。在第一个红色标记上方有空行。它标记了我输入消息的区域，按下回车键并写入了服务器响应。要看到它，我必须向下滚动到红色标记。然后是空行。第二个红色标记标记下一条消息将出现的区域。

如果你能帮我解决这个问题，我将不胜感激。

Answer 1

您确定收到短信了吗？您是否正确发送文本？你有任何错误吗？在数据广播之前设置断点，并在接收端设置断点，并检查您的变量是否包含您期望的内容。

这不是因为您正在尝试从没有任何数据的 Stream 中读取并为您提供虚拟数据导致应用程序打印没有文本的新行，因为它只是没有要发送的文本吗？

空文本的行数是否与您发送的字符串的长度相同？

Answer 2

我知道你的问题是这里的固定代码（在客户端）：

private static void getMessage()
{
    while (true)
    {
        serverStream = clientSocket.GetStream();
        int buffSize = 0;
        buffSize = clientSocket.Available;
        byte[] inStream = new byte[buffSize];
        serverStream.Read(inStream, 0, buffSize);
        string returndata = Encoding.ASCII.GetString(inStream);
        if (returndata != null)
        {
            readData = "" + returndata;
            msg();
        }
    }
}

您将缓冲区大小读入您想要可用字节的数组。

大卫

Answer 3

您的问题是 Encoding.ASCII.GetString 的误用：字节值 0 将被转换为 space，而不是您可能怀疑的 '[=12=]'。因为你用 10025 个零初始化它，所以你有一堆 space 填满你的行。在将 returndata 附加到 readData 之前修剪 returndata 将解决此问题，但会产生副作用，例如不允许在消息中前导和尾随 space。

你可以试试这个来理解问题：

static void Main(string[] args)
{
    byte[] lolempty = new byte[1024];
    string encoded = Encoding.ASCII.GetString(lolempty);
    Console.WriteLine(encoded.Length.ToString());
    Console.WriteLine("[{0}]", encoded);
}

写空行的聊天应用程序

Chat application writing empty lines

c#

client

chat

server