/*
C# Network Programming 
by Richard Blum

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

public class EmployeeSrvr
{
   public static void Main()
   {
      byte[] data = new byte[1024];
      TcpListener server = new TcpListener(9050);

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

      byte[] size = new byte[2];
      int recv = ns.Read(size, 0, 2);
      int packsize = BitConverter.ToInt16(size, 0);
      Console.WriteLine("packet size = {0}", packsize);
      recv = ns.Read(data, 0, packsize);

      Employee emp1 = new Employee(data);
      Console.WriteLine("emp1.EmployeeID = {0}", emp1.EmployeeID);
      Console.WriteLine("emp1.LastName = {0}", emp1.LastName);
      Console.WriteLine("emp1.FirstName = {0}", emp1.FirstName);
      Console.WriteLine("emp1.YearsService = {0}", emp1.YearsService);
      Console.WriteLine("emp1.Salary = {0}
", emp1.Salary);

      size = new byte[2];
      recv = ns.Read(size, 0, 2);
      packsize = BitConverter.ToInt16(size, 0);
      data = new byte[packsize];
      Console.WriteLine("packet size = {0}", packsize);
      recv = ns.Read(data, 0, packsize);

      Employee emp2 = new Employee(data);
      Console.WriteLine("emp2.EmployeeID = {0}", emp2.EmployeeID);
      Console.WriteLine("emp2.LastName = {0}", emp2.LastName);
      Console.WriteLine("emp2.FirstName = {0}", emp2.FirstName);
      Console.WriteLine("emp2.YearsService = {0}", emp2.YearsService);
      Console.WriteLine("emp2.Salary = {0}", emp2.Salary);

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

   }
}

public class Employee {
   public int EmployeeID;
   private int LastNameSize;
   public string LastName;
   private int FirstNameSize;
   public string FirstName;
   public int YearsService;
   public double Salary;
   public int size;

   public Employee()
   {
   }

   public Employee(byte[] data)
   {
      int place = 0;
      EmployeeID = BitConverter.ToInt32(data, place);
      place += 4;
      LastNameSize = BitConverter.ToInt32(data, place);
      place += 4;
      LastName = Encoding.ASCII.GetString(data, place, LastNameSize);
      place = place + LastNameSize;
      FirstNameSize = BitConverter.ToInt32(data, place);
      place += 4;
      FirstName = Encoding.ASCII.GetString(data, place, FirstNameSize);
      place += FirstNameSize;
      YearsService = BitConverter.ToInt32(data, place);
      place += 4;
      Salary = BitConverter.ToDouble(data, place);
   }

   public byte[] GetBytes()
   {
      byte[] data = new byte[1024];
      int place = 0;
      Buffer.BlockCopy(BitConverter.GetBytes(EmployeeID), 0, data, place, 4);
      place += 4;
      Buffer.BlockCopy(BitConverter.GetBytes(LastName.Length), 0, data, place, 4);
      place += 4;
      Buffer.BlockCopy(Encoding.ASCII.GetBytes(LastName), 0, data, place, LastName.Length);
      place += LastName.Length;
      Buffer.BlockCopy(BitConverter.GetBytes(FirstName.Length), 0, data, place, 4);
      place += 4;
      Buffer.BlockCopy(Encoding.ASCII.GetBytes(FirstName), 0, data, place, FirstName.Length);
      place += FirstName.Length;
      Buffer.BlockCopy(BitConverter.GetBytes(YearsService), 0, data, place, 4);
      place += 4;
      Buffer.BlockCopy(BitConverter.GetBytes(Salary), 0, data, place, 8);
      place += 8;
      size = place;
      return data;
   }
}

           
          

/*
C# Network Programming
by Richard Blum

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

public class VarTcpSrvr
{
private static int SendVarData(Socket s, byte[] data)
{
int total = 0;
int size = data.Length;
int dataleft = size;
int sent;

byte[] datasize = new byte[4];
datasize = BitConverter.GetBytes(size);
sent = s.Send(datasize);

while (total < size) { sent = s.Send(data, total, dataleft, SocketFlags.None); total += sent; dataleft -= sent; } return total; } private static byte[] ReceiveVarData(Socket s) { int total = 0; int recv; byte[] datasize = new byte[4]; recv = s.Receive(datasize, 0, 4, 0); int size = BitConverter.ToInt32(datasize, 0); int dataleft = size; byte[] data = new byte[size]; while(total < size) { recv = s.Receive(data, total, dataleft, 0); if (recv == 0) { data = Encoding.ASCII.GetBytes("exit "); break; } total += recv; dataleft -= recv; } return data; } public static void Main() { 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..."); 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); int sent = SendVarData(client, data); for (int i = 0; i < 5; i++) { data = ReceiveVarData(client); Console.WriteLine(Encoding.ASCII.GetString(data)); } Console.WriteLine("Disconnected from {0}", newclient.Address); client.Close(); newsock.Close(); } } [/csharp]

   

/*
C# Network Programming 
by Richard Blum

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

public class SimpleTcpSrvr
{
   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...");
      Socket client = newsock.Accept();
      IPEndPoint clientep =
                   (IPEndPoint)client.RemoteEndPoint;
      Console.WriteLine("Connected with {0} at port {1}",
                      clientep.Address, clientep.Port);

      
      string welcome = "Welcome to my test server";
      data = Encoding.ASCII.GetBytes(welcome);
      client.Send(data, data.Length,
                        SocketFlags.None);
      while(true)
      {
         data = new byte[1024];
         recv = client.Receive(data);
         if (recv == 0)
            break;
       
         Console.WriteLine(
                  Encoding.ASCII.GetString(data, 0, recv));
         client.Send(data, recv, SocketFlags.None);
      }
      Console.WriteLine("Disconnected from {0}",
                        clientep.Address);
      client.Close();
      newsock.Close();
   }
}

           
          

   

/*
C# Network Programming 
by Richard Blum

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

public class StreamTcpSrvr
{
   public static void Main()
   {
      string data;
      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...");

      Socket client = newsock.Accept();
      IPEndPoint newclient = (IPEndPoint)client.RemoteEndPoint;
      Console.WriteLine("Connected with {0} at port {1}",
                      newclient.Address, newclient.Port);

      NetworkStream ns = new NetworkStream(client);
      StreamReader sr = new StreamReader(ns);
      StreamWriter sw = new StreamWriter(ns);

      string welcome = "Welcome to my test server";
      sw.WriteLine(welcome);
      sw.Flush();

      while(true)
      {
         try
         {
            data = sr.ReadLine();
         } catch (IOException)
         {
            break;
         }
       
         Console.WriteLine(data);
         sw.WriteLine(data);
         sw.Flush();
      }
      Console.WriteLine("Disconnected from {0}", newclient.Address);
      sw.Close();
      sr.Close();
      ns.Close();
   }
}

           
          

/*
C# Network Programming
by Richard Blum

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

public class FixedTcpSrvr
{
private static int SendData(Socket s, byte[] data)
{
int total = 0;
int size = data.Length;
int dataleft = size;
int sent;

while (total < size) { sent = s.Send(data, total, dataleft, SocketFlags.None); total += sent; dataleft -= sent; } return total; } private static byte[] ReceiveData(Socket s, int size) { int total = 0; int dataleft = size; byte[] data = new byte[size]; int recv; while(total < size) { recv = s.Receive(data, total, dataleft, 0); if (recv == 0) { data = Encoding.ASCII.GetBytes("exit "); break; } total += recv; dataleft -= recv; } return data; } public static void Main() { 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..."); 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); int sent = SendData(client, data); for (int i = 0; i < 5; i++) { data = ReceiveData(client, 9); Console.WriteLine(Encoding.ASCII.GetString(data)); } Console.WriteLine("Disconnected from {0}", newclient.Address); client.Close(); newsock.Close(); } } [/csharp]

   

/*
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="Connect", Host="127.0.0.1",
     Port="All", Transport="All")]
[SocketPermission(SecurityAction.Deny, Access="Connect", Host="192.168.0.2",
     Port="All", Transport="All")]
[SocketPermission(SecurityAction.Deny, Access="Connect", Host="192.168.1.100",
     Port="80", Transport="All")]


public class PickyTcpClient
{
   public static void Main()
   {
      byte[] data = new byte[1024];
      string input, stringData;
      TcpClient server = null;

      Console.Write("Enter a host to connect to: ");
      string stringHost = Console.ReadLine();
 
      try
      {
         server = new TcpClient(stringHost, 9050);
      } catch (SocketException)
      {
         Console.WriteLine("Unable to connect to server");
         return;
      } catch (SecurityException)
      {
         Console.WriteLine(
            "Sorry, you are restricted from connecting to this server");
         return;
      }
      NetworkStream ns = server.GetStream();

      int recv = ns.Read(data, 0, data.Length);
      stringData = Encoding.ASCII.GetString(data, 0, recv);
      Console.WriteLine(stringData);

      while(true)
      {
         input = Console.ReadLine();
         if (input == "exit")
            break;
         ns.Write(Encoding.ASCII.GetBytes(input), 0, input.Length);
         ns.Flush();

         data = new byte[1024];
         recv = ns.Read(data, 0, data.Length);
         stringData = Encoding.ASCII.GetString(data, 0, recv);
         Console.WriteLine(stringData);
      }
      Console.WriteLine("Disconnecting from server...");
      ns.Close();
      server.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 SelectTcpClient
{
   public static void Main()
   {
      Socket sock = new Socket(AddressFamily.InterNetwork,
                        SocketType.Stream, ProtocolType.Tcp);
      IPEndPoint iep = new IPEndPoint(IPAddress.Parse("127.0.0.1"), 9050);
      byte[] data = new byte[1024];
      string stringData;
      int recv;

      sock.Connect(iep);
      Console.WriteLine("Connected to server");
      recv = sock.Receive(data);
      stringData = Encoding.ASCII.GetString(data, 0, recv);
      Console.WriteLine("Received: {0}", stringData);


      while(true)
      {
         stringData = Console.ReadLine();
         if (stringData == "exit")
            break;
         data = Encoding.ASCII.GetBytes(stringData);
         sock.Send(data, data.Length, SocketFlags.None);
         data = new byte[1024];
         recv = sock.Receive(data);
         stringData = Encoding.ASCII.GetString(data, 0, recv);
         Console.WriteLine("Received: {0}", stringData);
      }
      sock.Close();
   }
}