基于TCP的通信系统中的消息发送

Question

我正在开发一个基于TCP的通信系统。

我编写了一个用于发送Textmessages和远程打开MessageBox的工作函数。我想知道这段代码有多优雅，我可以如何改进它，因为在我看来，它似乎很混乱。

客户端：

private void btnSend_Click(object sender, EventArgs e)
{
    NetworkStream stream = client.GetStream();

    BinaryWriter w = new BinaryWriter(stream);

        byte[] msg = new byte[4096];
        msg = Encoding.ASCII.GetBytes("%" + txtMsg.Text + "&");

        w.Write(msg, 0, msg.Length);

}

private void btnMsgBox_Click(object sender, EventArgs e)
{
    NetworkStream stream = client.GetStream();

    byte[] msg = new byte[4096];          

    msg = Encoding.ASCII.GetBytes("%DisplayRemoteMessageBox&" + txtMsg.Text + "#");
    stream.Write(msg, 0, msg.Length);            
}

服务器：

while(true)
{
    while(client.Connected)
    {
        byte[] msg = new byte[4096];
        var count = stream.Read(msg, 0, msg.Length);

        string returnData = Encoding.ASCII.GetString(msg, 0, count);

        string command = returnData.Substring((returnData.IndexOf("%") + 1), (returnData.IndexOf("&") -1));


        switch(command)
        { 
        case "DisplayRemoteMessageBox":
                returnData = returnData.Replace("%DisplayRemoteMessageBox", "");
                int startInd = returnData.IndexOf("&");
                int len = returnData.IndexOf("#");                            

                returnData = returnData.Substring((startInd + 1), (len - 1));
                MessageBox((IntPtr)0, returnData, "TestBox", 0);
                 break;
        case "":                            
                client.Client.Disconnect(true);                        
                Console.WriteLine("User disconnected");
                 break;
        default:
                returnData = returnData.Substring(1, (returnData.Length - 2));
                Console.WriteLine(returnData);
                 break;
        }                 
    }
}

Answer 1

使用适当的名称

• returnData是什么？味精是什么？

不要覆盖相同的变量：

 byte[] msg = new byte[4096];
            msg = Encoding.ASCII.GetBytes("%" + txtMsg.Text + "&");

// You could simply do this instead:
   byte[] msg = Encoding.ASCII.GetBytes("%" + txtMsg.Text + "&");

// Also you’re reusing variables and overwriting. I don’t recommend this type of thing:

  string returnData = Encoding.ASCII.GetString(msg, 0, count);
            switch(command)
            { 
            case "DisplayRemoteMessageBox":
                    returnData = returnData.Replace("%DisplayRemoteMessageBox", ""); // don’t reset the returnData variable
                    returnData = returnData.Substring((startInd + 1), (len - 1));
            case "":                            
            default:
                    returnData = returnData.Substring(1, (returnData.Length - 2));
            }     

就

个人而言，我不会用您的代码更改任何东西.

但是如果你想做更多的事情，那么这里有一些想法。这是一个很好的练习--我会把它发到这里，否则看起来是浪费--但我认为它不必要地复杂了代码。保持您的代码原样。

internal class Program
{
    private static void Main(string[] args)
    {
    }

    #region Client Classes

    private ClientImplementation client = new ClientImplementation();
    private TextImplementation txtMsg = new TextImplementation();

    private void btnSend_Click_GiveAppropriateName1(object sender, EventArgs e)
    {
        // could use use a factory to get the writer
        Writer writer = new StandardWriter(client.GetStream(), txtMsg);
        writer.Write();
    }

    private void btnSend_ClickGiveAppropriateName2(object sender, EventArgs e)
    {
        Writer writer = new RemoteMessageBoxWriter(client.GetStream(), txtMsg);
        writer.Write();
    }

    public abstract class Writer
    {
        private BinaryWriter w;
        protected byte[] msg;
        protected TextImplementation txtMsg;

        public Writer(NetworkStream stream, TextImplementation txtMsg)
        {
            this.w = new BinaryWriter(stream);
            this.txtMsg = txtMsg;
            this.msg = GetBytes();
        }

        protected abstract byte[] GetBytes();

        public void Write()
        {
            w.Write(msg, 0, msg.Length);
        }
    }

    public class StandardWriter : Writer
    {
        public StandardWriter(NetworkStream stream, TextImplementation txtMsg)
            : base(stream, txtMsg)
        {
        }

        protected override byte[] GetBytes()
        {
            return Encoding.ASCII.GetBytes("%" + txtMsg.Text + "&");
        }
    }

    public class RemoteMessageBoxWriter : Writer
    {
        public RemoteMessageBoxWriter(NetworkStream stream, TextImplementation txtMsg)
            : base(stream, txtMsg)
        {
        }

        protected override byte[] GetBytes()
        {
            return Encoding.ASCII.GetBytes("%DisplayRemoteMessageBox&" + txtMsg.Text + "#");
        }
    }

    #endregion Client Classes

    #region Server Code

    public void Server()
    {
        while (true)
        {
            while (client.Connected)
            {
                HandleCommand command = new HandleCommandFactory().ReturnHandle(client.GetStream());
                command.DisplayData();
            }
        }
    }

    public class HandleCommandFactory
    {
        private NetworkStream stream;

        public HandleCommand ReturnHandle(NetworkStream stream)
        {
            this.stream = stream;
            string command = GetCommand(stream);

            switch (command)
            {
                case "DisplayRemoteMessageBox":
                    return new DisplayRemoteMsgBox();

                case "":
                    return new Disconnect();

                default:
                    return new Default();
            }
        }

        private string GetCommand(NetworkStream stream)
        {
            byte[] msg = new byte[4096];
            var count = this.stream.Read(msg, 0, msg.Length);
            string returnData = Encoding.ASCII.GetString(msg, 0, count);

            return returnData;
        }
    }

    abstract public class HandleCommand
    {
        protected string returnData;
        protected ClientImplementation client;

        abstract public void DisplayData();

        public HandleCommand()
        {
        }

        public HandleCommand(string returnData, ClientImplementation client)
        {
            this.returnData = returnData;
            this.client = client;
        }
    }

    public class Default : HandleCommand
    {
        public override void DisplayData()
        {
            string formattedData = returnData.Substring(1, (returnData.Length - 2));
            Console.WriteLine(formattedData);
        }
    }

    public class Disconnect : HandleCommand
    {
        public override void DisplayData()
        {
            client.Client.Disconnect(true);
            Console.WriteLine("User disconnected");
        }
    }

    public class DisplayRemoteMsgBox : HandleCommand
    {
        public override void DisplayData()
        {
            returnData = returnData.Replace("%DisplayRemoteMessageBox", "");
            int startInd = returnData.IndexOf("&");
            int len = returnData.IndexOf("#");

            string formattedData = returnData.Substring((startInd + 1), (len - 1));
            MessageBox((IntPtr)0, formattedData, "TestBox", 0);
        }

        private void MessageBox(IntPtr intPtr, string returnData, string p1, int p2)
        {
            throw new NotImplementedException();
        }
    }

    #endregion Server Code

    #region Additions just to make it compile

    public class ClientImplementation
    {
        public NetworkStream GetStream()
        {
            return new NetworkStream(GetSocket("blah", 0));
        }

        public bool Connected
        {
            get { return true; }
        }
    }

    public class TextImplementation
    {
        public string Text { get; set; }
    }

    private static Socket GetSocket(string server, int port)
    {
        Socket s = null;
        IPHostEntry hostEntry = null;

        // Get host related information.
        hostEntry = Dns.GetHostEntry(server);

        // Loop through the AddressList to obtain the supported AddressFamily. This is to avoid
        // an exception that occurs when the host IP Address is not compatible with the address family
        // (typical in the IPv6 case).
        foreach (IPAddress address in hostEntry.AddressList)
        {
            IPEndPoint ipe = new IPEndPoint(address, port);
            Socket tempSocket =
                new Socket(ipe.AddressFamily, SocketType.Stream, ProtocolType.Tcp);

            tempSocket.Connect(ipe);

            if (tempSocket.Connected)
            {
                s = tempSocket;
                break;
            }
            else
            {
                continue;
            }
        }
        return s;
    }

    #endregion Additions just to make it compile
}