/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/

using System;
using System.Net;
using System.Net.Sockets;
using System.Security;
using System.Security.Permissions;
using System.Text;

[SocketPermission(SecurityAction.Deny, Access="Accept", Host="0.0.0.0",
      Port="9050", Transport="All")]
[SocketPermission(SecurityAction.Deny, Access="Accept", Host="0.0.0.0",
      Port="9051", Transport="All")]
[SocketPermission(SecurityAction.Deny, Access="Accept", Host="0.0.0.0",
      Port="9052", Transport="All")]

public class PickyTcpListener
{
   public static void Main()
   {
      int recv;
      TcpListener newsock = null;
      byte[] data = new byte[1024];

      Console.Write("Enter port number to use: ");
      string stringPort = Console.ReadLine();
      int port = Convert.ToInt32(stringPort);

      try
      {
         newsock = new TcpListener(port);
         newsock.Start();
      } catch (SecurityException)
      {
         Console.WriteLine("Sorry, that port is unavailable");
         return;
      }
      Console.WriteLine("Waiting for a client...");

      TcpClient client = newsock.AcceptTcpClient();
      NetworkStream ns = client.GetStream();

      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      ns.Write(data, 0, data.Length);

      while(true)
      {
         data = new byte[1024];
         recv = ns.Read(data, 0, data.Length);
         if (recv == 0)
            break;
       
         Console.WriteLine(
                  Encoding.ASCII.GetString(data, 0, recv));
         ns.Write(data, 0, recv);
      }
      ns.Close();
      client.Close();
      newsock.Stop();
   }
}

           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/
using System;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Threading;

public class ThreadedTcpSrvr {
   private TcpListener client;

   public ThreadedTcpSrvr()
   {
      client = new TcpListener(9050);
      client.Start();

      Console.WriteLine("Waiting for clients...");
      while(true)
      {
         while (!client.Pending())
         {
            Thread.Sleep(1000);
         }

         ConnectionThread newconnection = new ConnectionThread();
         newconnection.threadListener = this.client;
         Thread newthread = new Thread(new
                   ThreadStart(newconnection.HandleConnection));
         newthread.Start();
      }
   }

   public static void Main()
   {
      ThreadedTcpSrvr server = new ThreadedTcpSrvr();
   }
}

class ConnectionThread
{
   public TcpListener threadListener;
   private static int connections = 0;

   public void HandleConnection()
   {
      int recv;
      byte[] data = new byte[1024];

      TcpClient client = threadListener.AcceptTcpClient();
      NetworkStream ns = client.GetStream();
      connections++;
      Console.WriteLine("New client accepted: {0} active connections",
                        connections);

      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      ns.Write(data, 0, data.Length);

      while(true)
      {
         data = new byte[1024];
         recv = ns.Read(data, 0, data.Length);
         if (recv == 0)
            break;
      
         ns.Write(data, 0, recv);
      }
      ns.Close();
      client.Close();
      connections--;
      Console.WriteLine("Client disconnected: {0} active connections",
                         connections);
   }
}

           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class TcpPollSrvr {
   public static void Main()
   {
      int recv;
      byte[] data = new byte[1024];
      IPEndPoint ipep = new IPEndPoint(IPAddress.Any,
                             9050);

      Socket newsock = new
          Socket(AddressFamily.InterNetwork,
                      SocketType.Stream, ProtocolType.Tcp);

      newsock.Bind(ipep);
      newsock.Listen(10);
      Console.WriteLine("Waiting for a client...");
      bool result;
      int i = 0;
      while(true)
      {
         i++;
         Console.WriteLine("polling for accept#{0}...", i);
         result = newsock.Poll(1000000, SelectMode.SelectRead);
         if (result)
         {
            break;
         }
      }
      Socket client = newsock.Accept();

      IPEndPoint newclient =
                   (IPEndPoint)client.RemoteEndPoint;
      Console.WriteLine("Connected with {0} at port {1}",
                      newclient.Address, newclient.Port);
  
      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      client.Send(data, data.Length,
                        SocketFlags.None);
      
      i = 0;
      while(true)
      {
         Console.WriteLine("polling for receive #{0}...", i);
         i++;
         result = client.Poll(3000000, SelectMode.SelectRead);
         if(result)
         {
            data = new byte[1024];
            i = 0;
            recv = client.Receive(data);
            if (recv == 0)
               break;
       
            Console.WriteLine(
                  Encoding.ASCII.GetString(data, 0, recv));
            client.Send(data, recv, 0);
         }
      }

      Console.WriteLine("Disconnected from {0}",
                        newclient.Address);
      client.Close();
      newsock.Close();
   }
}
           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/
using System;
using System.Collections;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class SelectTcpSrvr
{
   public static void Main()
   {
      ArrayList sockList = new ArrayList(2);
      ArrayList copyList = new ArrayList(2);
      Socket main = new Socket(AddressFamily.InterNetwork,
                         SocketType.Stream, ProtocolType.Tcp);

      IPEndPoint iep = new IPEndPoint(IPAddress.Any, 9050);
      byte[] data = new byte[1024];
      string stringData;
      int recv;


      main.Bind(iep);
      main.Listen(2);

      Console.WriteLine("Waiting for 2 clients...");
      Socket client1 = main.Accept();
      IPEndPoint iep1 = (IPEndPoint)client1.RemoteEndPoint;
      client1.Send(Encoding.ASCII.GetBytes("Welcome to the server"));
      Console.WriteLine("Connected to {0}", iep1.ToString());
      sockList.Add(client1);

      Console.WriteLine("Waiting for 1 more client...");
      Socket client2 = main.Accept();
      IPEndPoint iep2 = (IPEndPoint)client2.RemoteEndPoint;
      Console.WriteLine("Connected to {0}", iep2.ToString());    
      client2.Send(Encoding.ASCII.GetBytes("Welcome to the server"));
      sockList.Add(client2);
      main.Close();

      while(true)
      {
         copyList = new ArrayList(sockList);
         Console.WriteLine("Monitoring {0} sockets...", copyList.Count);
         Socket.Select(copyList, null, null, 10000000);

         foreach(Socket client in copyList)
         {
            
            data = new byte[1024];
            recv = client.Receive(data);
            stringData = Encoding.ASCII.GetString(data, 0, recv);
            Console.WriteLine("Received: {0}", stringData);
            if (recv == 0)
            {
               iep = (IPEndPoint)client.RemoteEndPoint;
               Console.WriteLine("Client {0} disconnected.", iep.ToString());
               client.Close();
               sockList.Remove(client);
               if (sockList.Count == 0)
               {
                  Console.WriteLine("Last client disconnected, bye");
                  return;
               }
            }
            else
               client.Send(data, recv, SocketFlags.None);
         }
      }
   }
}

           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/

using System;
using System.Drawing;
using System.Net;
using System.Net.Sockets;
using System.Text;
using System.Windows.Forms;


public class AsyncTcpSrvr : Form
{
   private TextBox conStatus;
   private ListBox results;
   private byte[] data = new byte[1024];
   private int size = 1024;
   private Socket server;


   public AsyncTcpSrvr()
   {
      Text = "Asynchronous TCP Server";
      Size = new Size(400, 380);

      results = new ListBox();
      results.Parent = this;
      results.Location = new Point(10, 65);
      results.Size = new Size(350, 20 * Font.Height);

      Label label1 = new Label();
      label1.Parent = this;
      label1.Text = "Text received from client:";
      label1.AutoSize = true;
      label1.Location = new Point(10, 45);

      Label label2 = new Label();
      label2.Parent = this;
      label2.Text = "Connection Status:";
      label2.AutoSize = true;
      label2.Location = new Point(10, 330);

      conStatus = new TextBox();
      conStatus.Parent = this;
      conStatus.Text = "Waiting for client...";
      conStatus.Size = new Size(200, 2 * Font.Height);
      conStatus.Location = new Point(110, 325);

      Button stopServer = new Button();
      stopServer.Parent = this;
      stopServer.Text = "Stop Server";
      stopServer.Location = new Point(260,32);
      stopServer.Size = new Size(7 * Font.Height, 2 * Font.Height);
      stopServer.Click += new EventHandler(ButtonStopOnClick);

      server = new Socket(AddressFamily.InterNetwork,
                    SocketType.Stream, ProtocolType.Tcp);
      IPEndPoint iep = new IPEndPoint(IPAddress.Any, 9050);
      server.Bind(iep);
      server.Listen(5);
      server.BeginAccept(new AsyncCallback(AcceptConn), server);
   }

   void ButtonStopOnClick(object obj, EventArgs ea)
   {
      Close();
   }

   void AcceptConn(IAsyncResult iar)
   {
      Socket oldserver = (Socket)iar.AsyncState;
      Socket client = oldserver.EndAccept(iar);
      conStatus.Text = "Connected to: " + client.RemoteEndPoint.ToString();
      string stringData = "Welcome to my server";
      byte[] message1 = Encoding.ASCII.GetBytes(stringData);
      client.BeginSend(message1, 0, message1.Length, SocketFlags.None,
                  new AsyncCallback(SendData), client);
   }

   void SendData(IAsyncResult iar)
   {
      Socket client = (Socket)iar.AsyncState;
      int sent = client.EndSend(iar);
      client.BeginReceive(data, 0, size, SocketFlags.None,
                  new AsyncCallback(ReceiveData), client);
   }

   void ReceiveData(IAsyncResult iar)
   {
      Socket client = (Socket)iar.AsyncState;
      int recv = client.EndReceive(iar);
      if (recv == 0)
      {
         client.Close();
         conStatus.Text = "Waiting for client...";
         server.BeginAccept(new AsyncCallback(AcceptConn), server);
         return;
      }
      string receivedData = Encoding.ASCII.GetString(data, 0, recv);
      results.Items.Add(receivedData);
      byte[] message2 = Encoding.ASCII.GetBytes(receivedData);
      client.BeginSend(message2, 0, message2.Length, SocketFlags.None,
                   new AsyncCallback(SendData), client);
   }

   public static void Main()
   {
      Application.Run(new AsyncTcpSrvr());
   }
}
           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class TcpListenerSample
{
   public static void Main()
   {
      int recv;
      byte[] data = new byte[1024];

      TcpListener newsock = new TcpListener(9050);
      newsock.Start();
      Console.WriteLine("Waiting for a client...");

      TcpClient client = newsock.AcceptTcpClient();
      NetworkStream ns = client.GetStream();

      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      ns.Write(data, 0, data.Length);

      while(true)
      {
         data = new byte[1024];
         recv = ns.Read(data, 0, data.Length);
         if (recv == 0)
            break;
       
         Console.WriteLine(
                  Encoding.ASCII.GetString(data, 0, recv));
         ns.Write(data, 0, recv);
      }
      ns.Close();
      client.Close();
      newsock.Stop();
   }
}
           
          

   

/*
C# Network Programming 
by Richard Blum

Publisher: Sybex 
ISBN: 0782141765
*/

using System;
using System.Net;
using System.Net.Sockets;
using System.Text;

public class NetworkOrderSrvr
{
   public static void Main()
   {
      int recv;
      byte[] data = new byte[1024];

      TcpListener server = new TcpListener(9050);
      server.Start();
      Console.WriteLine("waiting for a client...");

      TcpClient client = server.AcceptTcpClient();
      NetworkStream ns = client.GetStream();

      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      ns.Write(data, 0, data.Length);
      ns.Flush();

      data = new byte[2];
      recv = ns.Read(data, 0, data.Length);
      short test1t = BitConverter.ToInt16(data, 0);
      short test1 = IPAddress.NetworkToHostOrder(test1t);
      Console.WriteLine("received test1 = {0}", test1);

      data = new byte[4];
      recv = ns.Read(data, 0, data.Length);
      int test2t = BitConverter.ToInt32(data, 0);
      int test2 = IPAddress.NetworkToHostOrder(test2t);
      Console.WriteLine("received test2 = {0}", test2);

      data = new byte[8];
      recv = ns.Read(data, 0, data.Length);
      long test3t = BitConverter.ToInt64(data, 0);
      long test3 = IPAddress.NetworkToHostOrder(test3t);
      Console.WriteLine("received test3 = {0}", test3);

      ns.Close();
      client.Close();
      server.Stop();
   }
}