SocketSamples.txt

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20200520

/*

參考  
Network Programming in the .NET Framework.pdf
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/?view=netframework-4.6

包含:
同步用戶端通訊範例 Synchronous Client Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/synchronous-client-socket-example?view=netframework-4.6

同步伺服器端通訊範例 Synchronous Server Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/synchronous-server-socket-example?view=netframework-4.6

非同步用戶端通訊範例 Asynchronous Client Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/asynchronous-client-socket-example?view=netframework-4.6

非同步伺服器端通訊範例 Asynchronous Server Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/asynchronous-server-socket-example?view=netframework-4.6

*/


----------
同步用戶端通訊範例 Synchronous Client Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/synchronous-client-socket-example?view=netframework-4.6

The following example program creates a client that connects to a server. The client is built with a synchronous socket, so execution of the client application is suspended until the server returns a response. The application sends a string to the server and then displays the string returned by the server on the console.

using System;  
using System.Net;  
using System.Net.Sockets;  
using System.Text;  
  
public class SynchronousSocketClient {  
  
    public static void StartClient() {  
        // Data buffer for incoming data.  
        byte[] bytes = new byte[1024];  
  
        // Connect to a remote device.  
        try {  
            // Establish the remote endpoint for the socket.  
            // This example uses port 11000 on the local computer.  
            IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());  
            IPAddress ipAddress = ipHostInfo.AddressList[0];  
            IPEndPoint remoteEP = new IPEndPoint(ipAddress,11000);  
  
            // Create a TCP/IP  socket.  
            Socket sender = new Socket(ipAddress.AddressFamily,
                SocketType.Stream, ProtocolType.Tcp );  
  
            // Connect the socket to the remote endpoint. Catch any errors.  
            try {  
                sender.Connect(remoteEP);  
  
                Console.WriteLine("Socket connected to {0}",  
                    sender.RemoteEndPoint.ToString());  
  
                // Encode the data string into a byte array.  
                byte[] msg = Encoding.ASCII.GetBytes("This is a test<EOF>");  
  
                // Send the data through the socket.  
                int bytesSent = sender.Send(msg);  
  
                // Receive the response from the remote device.  
                int bytesRec = sender.Receive(bytes);  
                Console.WriteLine("Echoed test = {0}",  
                    Encoding.ASCII.GetString(bytes,0,bytesRec));  
  
                // Release the socket.  
                sender.Shutdown(SocketShutdown.Both);  
                sender.Close();  
  
            } catch (ArgumentNullException ane) {  
                Console.WriteLine("ArgumentNullException : {0}",ane.ToString());  
            } catch (SocketException se) {  
                Console.WriteLine("SocketException : {0}",se.ToString());  
            } catch (Exception e) {  
                Console.WriteLine("Unexpected exception : {0}", e.ToString());  
            }  
  
        } catch (Exception e) {  
            Console.WriteLine( e.ToString());  
        }  
    }  
  
    public static int Main(String[] args) {  
        StartClient();  
        return 0;  
    }  
}

----------
同步伺服器端通訊範例 Synchronous Server Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/synchronous-server-socket-example?view=netframework-4.6

The following example program creates a server that receives connection requests from clients. The server is built with a synchronous socket, so execution of the server application is suspended while it waits for a connection from a client. The application receives a string from the client, displays the string on the console, and then echoes the string back to the client. The string from the client must contain the string "<EOF>" to signal the end of the message.

using System;  
using System.Net;  
using System.Net.Sockets;  
using System.Text;  
  
public class SynchronousSocketListener {  
  
    // Incoming data from the client.  
    public static string data = null;  
  
    public static void StartListening() {  
        // Data buffer for incoming data.  
        byte[] bytes = new Byte[1024];  
  
        // Establish the local endpoint for the socket.  
        // Dns.GetHostName returns the name of the
        // host running the application.  
        IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());  
        IPAddress ipAddress = ipHostInfo.AddressList[0];  
        IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);  
  
        // Create a TCP/IP socket.  
        Socket listener = new Socket(ipAddress.AddressFamily,  
            SocketType.Stream, ProtocolType.Tcp );  
  
        // Bind the socket to the local endpoint and
        // listen for incoming connections.  
        try {  
            listener.Bind(localEndPoint);  
            listener.Listen(10);  
  
            // Start listening for connections.  
            while (true) {  
                Console.WriteLine("Waiting for a connection...");  
                // Program is suspended while waiting for an incoming connection.  
                Socket handler = listener.Accept();  
                data = null;  
  
                // An incoming connection needs to be processed.  
                while (true) {  
                    int bytesRec = handler.Receive(bytes);  
                    data += Encoding.ASCII.GetString(bytes,0,bytesRec);  
                    if (data.IndexOf("<EOF>") > -1) {  
                        break;  
                    }  
                }  
  
                // Show the data on the console.  
                Console.WriteLine( "Text received : {0}", data);  
  
                // Echo the data back to the client.  
                byte[] msg = Encoding.ASCII.GetBytes(data);  
  
                handler.Send(msg);  
                handler.Shutdown(SocketShutdown.Both);  
                handler.Close();  
            }  
  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
  
        Console.WriteLine("\nPress ENTER to continue...");  
        Console.Read();  
  
    }  
  
    public static int Main(String[] args) {  
        StartListening();  
        return 0;  
    }  
}


----------
非同步用戶端通訊範例 Asynchronous Client Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/asynchronous-client-socket-example?view=netframework-4.6

The following example program creates a client that connects to a server. The client is built with an asynchronous socket, so execution of the client application is not suspended while the server returns a response. The application sends a string to the server and then displays the string returned by the server on the console.

using System;  
using System.Net;  
using System.Net.Sockets;  
using System.Threading;  
using System.Text;  
  
// State object for receiving data from remote device.  
public class StateObject {  
    // Client socket.  
    public Socket workSocket = null;  
    // Size of receive buffer.  
    public const int BufferSize = 256;  
    // Receive buffer.  
    public byte[] buffer = new byte[BufferSize];  
    // Received data string.  
    public StringBuilder sb = new StringBuilder();  
}  
  
public class AsynchronousClient {  
    // The port number for the remote device.  
    private const int port = 11000;  
  
    // ManualResetEvent instances signal completion.  
    private static ManualResetEvent connectDone =
        new ManualResetEvent(false);  
    private static ManualResetEvent sendDone =
        new ManualResetEvent(false);  
    private static ManualResetEvent receiveDone =
        new ManualResetEvent(false);  
  
    // The response from the remote device.  
    private static String response = String.Empty;  
  
    private static void StartClient() {  
        // Connect to a remote device.  
        try {  
            // Establish the remote endpoint for the socket.  
            // The name of the
            // remote device is "host.contoso.com".  
            IPHostEntry ipHostInfo = Dns.GetHostEntry("host.contoso.com");  
            IPAddress ipAddress = ipHostInfo.AddressList[0];  
            IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);  
  
            // Create a TCP/IP socket.  
            Socket client = new Socket(ipAddress.AddressFamily,  
                SocketType.Stream, ProtocolType.Tcp);  
  
            // Connect to the remote endpoint.  
            client.BeginConnect( remoteEP,
                new AsyncCallback(ConnectCallback), client);  
            connectDone.WaitOne();  
  
            // Send test data to the remote device.  
            Send(client,"This is a test<EOF>");  
            sendDone.WaitOne();  
  
            // Receive the response from the remote device.  
            Receive(client);  
            receiveDone.WaitOne();  
  
            // Write the response to the console.  
            Console.WriteLine("Response received : {0}", response);  
  
            // Release the socket.  
            client.Shutdown(SocketShutdown.Both);  
            client.Close();  
  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    private static void ConnectCallback(IAsyncResult ar) {  
        try {  
            // Retrieve the socket from the state object.  
            Socket client = (Socket) ar.AsyncState;  
  
            // Complete the connection.  
            client.EndConnect(ar);  
  
            Console.WriteLine("Socket connected to {0}",  
                client.RemoteEndPoint.ToString());  
  
            // Signal that the connection has been made.  
            connectDone.Set();  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    private static void Receive(Socket client) {  
        try {  
            // Create the state object.  
            StateObject state = new StateObject();  
            state.workSocket = client;  
  
            // Begin receiving the data from the remote device.  
            client.BeginReceive( state.buffer, 0, StateObject.BufferSize, 0,  
                new AsyncCallback(ReceiveCallback), state);  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    private static void ReceiveCallback( IAsyncResult ar ) {  
        try {  
            // Retrieve the state object and the client socket
            // from the asynchronous state object.  
            StateObject state = (StateObject) ar.AsyncState;  
            Socket client = state.workSocket;  
  
            // Read data from the remote device.  
            int bytesRead = client.EndReceive(ar);  
  
            if (bytesRead > 0) {  
                // There might be more data, so store the data received so far.  
            state.sb.Append(Encoding.ASCII.GetString(state.buffer,0,bytesRead));  
  
                // Get the rest of the data.  
                client.BeginReceive(state.buffer,0,StateObject.BufferSize,0,  
                    new AsyncCallback(ReceiveCallback), state);  
            } else {  
                // All the data has arrived; put it in response.  
                if (state.sb.Length > 1) {  
                    response = state.sb.ToString();  
                }  
                // Signal that all bytes have been received.  
                receiveDone.Set();  
            }  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    private static void Send(Socket client, String data) {  
        // Convert the string data to byte data using ASCII encoding.  
        byte[] byteData = Encoding.ASCII.GetBytes(data);  
  
        // Begin sending the data to the remote device.  
        client.BeginSend(byteData, 0, byteData.Length, 0,  
            new AsyncCallback(SendCallback), client);  
    }  
  
    private static void SendCallback(IAsyncResult ar) {  
        try {  
            // Retrieve the socket from the state object.  
            Socket client = (Socket) ar.AsyncState;  
  
            // Complete sending the data to the remote device.  
            int bytesSent = client.EndSend(ar);  
            Console.WriteLine("Sent {0} bytes to server.", bytesSent);  
  
            // Signal that all bytes have been sent.  
            sendDone.Set();  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    public static int Main(String[] args) {  
        StartClient();  
        return 0;  
    }  
}




----------
非同步伺服器端通訊範例 Asynchronous Server Socket Example
https://docs.microsoft.com/zh-tw/dotnet/framework/network-programming/asynchronous-server-socket-example?view=netframework-4.6

The following example program creates a server that receives connection requests from clients. The server is built with an asynchronous socket, so execution of the server application is not suspended while it waits for a connection from a client. The application receives a string from the client, displays the string on the console, and then echoes the string back to the client. The string from the client must contain the string "<EOF>" to signal the end of the message.
伺服器等待用戶端連線時, 不會封鎖執行.
本範例會等待用戶端傳入"<EOF>"通知訊息傳送完畢.

using System;  
using System.Net;  
using System.Net.Sockets;  
using System.Text;  
using System.Threading;  
  
// State object for reading client data asynchronously  
public class StateObject {  
    // Client  socket.  
    public Socket workSocket = null;  
    // Size of receive buffer.  
    public const int BufferSize = 1024;  
    // Receive buffer.  
    public byte[] buffer = new byte[BufferSize];  
// Received data string.  
    public StringBuilder sb = new StringBuilder();
}  
  
public class AsynchronousSocketListener {  
    // Thread signal.  
    public static ManualResetEvent allDone = new ManualResetEvent(false);  
  
    public AsynchronousSocketListener() {  
    }  
  
    public static void StartListening() {  
        // Establish the local endpoint for the socket.  
        // The DNS name of the computer  
        // running the listener is "host.contoso.com".  
        IPHostEntry ipHostInfo = Dns.GetHostEntry(Dns.GetHostName());  
        IPAddress ipAddress = ipHostInfo.AddressList[0];  
        IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);  
  
        // Create a TCP/IP socket.  
        Socket listener = new Socket(ipAddress.AddressFamily,  
            SocketType.Stream, ProtocolType.Tcp );  
  
        // Bind the socket to the local endpoint and listen for incoming connections.  
        try {  
            listener.Bind(localEndPoint);  
            listener.Listen(100);  
  
            while (true) {  
                // Set the event to nonsignaled state.  
                allDone.Reset();  
  
                // Start an asynchronous socket to listen for connections.  
                Console.WriteLine("Waiting for a connection...");  
                listener.BeginAccept(
                    new AsyncCallback(AcceptCallback),  
                    listener );  
  
                // Wait until a connection is made before continuing.  
                allDone.WaitOne();  
            }  
  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
  
        Console.WriteLine("\nPress ENTER to continue...");  
        Console.Read();  
  
    }  
  
    public static void AcceptCallback(IAsyncResult ar) {  
        // Signal the main thread to continue.  
        allDone.Set();  
  
        // Get the socket that handles the client request.  
        Socket listener = (Socket) ar.AsyncState;  
        Socket handler = listener.EndAccept(ar);  
  
        // Create the state object.  
        StateObject state = new StateObject();  
        state.workSocket = handler;  
        handler.BeginReceive( state.buffer, 0, StateObject.BufferSize, 0,  
            new AsyncCallback(ReadCallback), state);  
    }  
  
    public static void ReadCallback(IAsyncResult ar) {  
        String content = String.Empty;  
  
        // Retrieve the state object and the handler socket  
        // from the asynchronous state object.  
        StateObject state = (StateObject) ar.AsyncState;  
        Socket handler = state.workSocket;  
  
        // Read data from the client socket.
        int bytesRead = handler.EndReceive(ar);  
  
        if (bytesRead > 0) {  
            // There  might be more data, so store the data received so far.  
            state.sb.Append(Encoding.ASCII.GetString(  
                state.buffer, 0, bytesRead));  
  
            // Check for end-of-file tag. If it is not there, read
            // more data.  
            content = state.sb.ToString();  
            if (content.IndexOf("<EOF>") > -1) {  
                // All the data has been read from the
                // client. Display it on the console.  
                Console.WriteLine("Read {0} bytes from socket. \n Data : {1}",  
                    content.Length, content );  
                // Echo the data back to the client.  
                Send(handler, content);  
            } else {  
                // Not all data received. Get more.  
                handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,  
                new AsyncCallback(ReadCallback), state);  
            }  
        }  
    }  
  
    private static void Send(Socket handler, String data) {  
        // Convert the string data to byte data using ASCII encoding.  
        byte[] byteData = Encoding.ASCII.GetBytes(data);  
  
        // Begin sending the data to the remote device.  
        handler.BeginSend(byteData, 0, byteData.Length, 0,  
            new AsyncCallback(SendCallback), handler);  
    }  
  
    private static void SendCallback(IAsyncResult ar) {  
        try {  
            // Retrieve the socket from the state object.  
            Socket handler = (Socket) ar.AsyncState;  
  
            // Complete sending the data to the remote device.  
            int bytesSent = handler.EndSend(ar);  
            Console.WriteLine("Sent {0} bytes to client.", bytesSent);  
  
            handler.Shutdown(SocketShutdown.Both);  
            handler.Close();  
  
        } catch (Exception e) {  
            Console.WriteLine(e.ToString());  
        }  
    }  
  
    public static int Main(String[] args) {  
        StartListening();  
        return 0;  
    }  
}