学步园

下面的示例程序创建一个连接到服务器的客户端。该客户端是用同步套接字生成的，因此挂起客户端应用程序的执行，直到服务器返回响应为止。该应用程序将字符串发送到服务器，然后在控制台显示该服务器返回的字符串。

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.Resolve(Dns.GetHostName())
            IPAddress ipAddress = ipHostInfo.AddressList[0];
            IPEndPoint remoteEP = new IPEndPoint(ipAddress,11000);

            // Create a TCP/IP  socket.
            Socket sender = new Socket(AddressFamily.InterNetwork, 
                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;
    }
}

下面的示例程序创建一个接收来自客户端的连接请求的服务器。该服务器是用同步套接字生成的，因此在等待来自客户端的连接时挂起服务器应用程序的执行。
该应用程序接收来自客户端的字符串，在控制台显示该字符串，然后将该字符串回显到客户端。来自客户端的字符串必须包含字符串“<EOF>”，以发出表示消息结尾的信号。
 
 
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.Resolve(Dns.GetHostName());
        IPAddress ipAddress = ipHostInfo.AddressList[0];
        IPEndPoint localEndPoint = new IPEndPoint(ipAddress, 11000);

        // Create a TCP/IP socket.
        Socket listener = new Socket(AddressFamily.InterNetwork,
            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) {
                    bytes = new byte[1024];
                    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;
    }
}