INGINERIA PROGRAMARII LUCRARE DE LABORATOR

Obiective

Insusirea modului de lucru cu reteaua utilizand C#.

Obtinerea si afisarea hostname-ului si a adresei IP folosind C#.

Insusirea modului de lucru cu cu socket-uri sincrone si asincrone.

1. Obtinerea si afisarea hostname-ului si a adresei IP folosind C#.

2.1Studiati si testati urmatorul cod sursa C#:

using System;

using System.Net;

namespace HostnameAndIP

public static string getIP(string hostname)

public static void Main()

}

2. Insusirea modului de lucru cu cu socket-uri sincrone

2.1Socketr-ul server. Studiati si testati urmatorul cod sursa C#:

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

public class SocketServer

}

//Afisarea datelor primite

Console.WriteLine('Text primit : ', clientData);

// Si trimiterea acesteia inapoi

byte[] msg = Encoding.ASCII.GetBytes(clientData);

handler.Send(msg);

handler.Shutdown(SocketShutdown.Both);

handler.Close();

}

catch (Exception e)

Console.WriteLine('nApasati ENTER pentru a continua');

Console.Read();

}

public static int Main(String[] args)

2.2Socketr-ul client. Studiati si testati urmatorul cod sursa C#:

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

public class SocketClient

public static void StartClient() {

// Buffer pentru datele care vin dinspre server

byte[] buffer = new byte[1024];

try {

// Stabilirea EndPoint-ului pentru client

IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());

IPAddress ipAddress = ipHostInfo.AddressList[0];

IPEndPoint remoteEndPoint = new IPEndPoint(ipAddress,1234);

// // Crearea socket-ului TCP/IP

Socket sender = new Socket(AddressFamily.InterNetwork,

SocketType.Stream, ProtocolType.Tcp );

// Conectare la server

try {

sender.Connect(remoteEndPoint);

Console.WriteLine('Socket connected to ',

sender.RemoteEndPoint.ToString());

byte[] msg = Encoding.ASCII.GetBytes('Acesta este un

test<EOF>');

// Trimiterea datelor

int bytesSent = sender.Send(msg);

// Primirea raspunsului de la server

int bytesReceptionati = sender.Receive(buffer);

Console.WriteLine('Echoed test = ',

Encoding.ASCII.GetString(buffer, 0,

bytesReceptionati));

// Release the socket.

sender.Shutdown(SocketShutdown.Both);

Referat: Contabilitatea tertilor Referat: Structurarea elementelor de activ si pasiv dupa criterii financiare

sender.Close();

} catch (ArgumentNullException ane) {

Console.WriteLine('ArgumentNullException :

',ane.ToString());

} catch (SocketException se) {

Console.WriteLine('SocketException :

',se.ToString());

} catch (Exception e) {

Console.WriteLine('Unexpected exception : ',

e.ToString());

} catch (Exception e)

}

public static int Main(String[] args)

2.3Modificati cele doua programe astfel incat:

transmisia datelor sa fie efectuata pe portul 65535;

datele trimise de la nivelul socket-ului client sa fie citite de la tastatura;

socket-ul server sa trimita inapoi sirul de caractere format din majuscule;

comunicatia sa se termine la introducerea textului "EXIT" la nivelul clientului.

3. Insusirea modului de lucru cu cu socket-uri asincrone

3.1Socketr-ul server. Studiati si testati urmatorul cod sursa C#:

using System;

using System.Net;

using System.Net.Sockets;

using System.Text;

using System.Threading;

public class StateObject

public class SocketServerAsincron

public static void StartListening()

}

catch (Exception e)

Console.WriteLine('nApasati ENTER pentru a continua');

Console.Read();

}

public static void AcceptCallback(IAsyncResult ar)

public static void ReadCallback(IAsyncResult ar)

{

String content = String.Empty;

StateObject state = (StateObject)ar.AsyncState;

Socket handler = state.workSocket;

int bytesRead = handler.EndReceive(ar);

if (bytesRead > 0)

{

state.sb.Append(Encoding.ASCII.GetString(

state.buffer, 0, bytesRead));

content = state.sb.ToString();

if (content.IndexOf('<GATA>') > -1)

Console.WriteLine('Am citit octeti. n Date primite

: ', content.Length, content);

Send(handler, content);

else

}

}

private static void Send(Socket handler, String data)

private static void SendCallback(IAsyncResult ar)

{

try

{

Socket handler = (Socket)ar.AsyncState;

int bytesSent = handler.EndSend(ar);

Console.WriteLine('Sent bytes to client.', bytesSent);

handler.Shutdown(SocketShutdown.Both);

handler.Close();

}

catch (Exception e)

}

public static int Main(String[] args)

3.2Socketr-ul client. Studiati si testati urmatorul cod sursa C#:

using System;

using System.Net;

using System.Net.Sockets;

using System.Threading;

using System.Text;

public class StateObject

public class AsynchronousClient {

private const int port = 1234;

private static ManualResetEvent connectDone =

new ManualResetEvent(false);

private static ManualResetEvent sendDone =

new ManualResetEvent(false);

private static ManualResetEvent receiveDone =

new ManualResetEvent(false);

private static String response = String.Empty;

private static void StartClient() {

try {

IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());

IPAddress ipAddress = ipHostInfo.AddressList[0];

IPEndPoint remoteEP = new IPEndPoint(ipAddress, port);

Socket client = new Socket(AddressFamily.InterNetwork,

SocketType.Stream, ProtocolType.Tcp);

client.BeginConnect( remoteEP,

new AsyncCallback(ConnectCallback), client);

connectDone.WaitOne();

// Trimitere date de test

Send(client,'This is a test<GATA>');

sendDone.WaitOne();

Receive(client);

receiveDone.WaitOne();

Console.WriteLine('Raspuns primit de la server : ',

response);

client.Shutdown(SocketShutdown.Both);

client.Close();

} catch (Exception e)

}

private static void ConnectCallback(IAsyncResult ar) {

try {

Socket client = (Socket) ar.AsyncState;

client.EndConnect(ar);

Console.WriteLine('Socket conectat la ',

client.RemoteEndPoint.ToString());

connectDone.Set();

} catch (Exception e)

}

private static void Receive(Socket client) catch (Exception e)

}

private static void ReceiveCallback( IAsyncResult ar ) else

receiveDone.Set();

} catch (Exception e)

}

private static void Send(Socket client, String data)

private static void SendCallback(IAsyncResult ar) {

try {

Socket client = (Socket) ar.AsyncState;

int bytesSent = client.EndSend(ar);

Console.WriteLine('Am trimis octeti spre server.',

bytesSent);

sendDone.Set();

} catch (Exception e)

}

public static int Main(String[] args)

3.3Explicati necesitatea functiilor:

La nivelul serverului:

public static void StartListening()

public static void AcceptCallback(IAsyncResult ar)

public static void ReadCallback(IAsyncResult ar)

private static void Send(Socket handler, String data)

private static void SendCallback(IAsyncResult ar)

La nivelul clientului:

• public static void StartListening()
• private static void ConnectCallback(IAsyncResult ar)
• private static void Receive(Socket client)
• private static void ReceiveCallback( IAsyncResult ar )
• private static void Send(Socket client, String data)
• private static void SendCallback(IAsyncResult ar)

3.4Modificati cele doua programe astfel incat:

transmisia datelor sa fie efectuata pe portul 2345;

datele trimise de la nivelul socket-ului client sa fie citite de la tastatura;

socket-ul server sa trimita inapoi doar lungimea textului primit;

comunicatia sa se termine la introducerea textului "EOF" la nivelul clientului.

3.5 Testati aplicatiile modificate lansand in executie un singur server si clienti multipli.

Teme:

1.    Creati o aplicatie C# de tip server socket asincron si una de tip client socket asincron cu ajutorul carora doi utilizatori aflati pe computere diferite sa poata conversa. Pentru dezvoltarea interfetelor grafice puteti urma exemplele: