Imports System
Imports System.IO
Imports System.Net
Imports System.Net.Sockets
Imports System.Text
Imports Microsoft.VisualBasic

Public Class Form1

      Sub Connect(ByVal server As [String], ByVal message As [String])

        Try

            'Creazione dell'oggetto client
            Dim port As Int32 = 2000
            Dim client As New Sockets.TcpClient(server, port)

            'Converto il messaggio passato come ASCII e lo memorizzo in un array 
            Dim data As [Byte]() = System.Text.Encoding.ASCII.GetBytes(message)

            'Avvio un canale per inviare e ricevere
            Dim stream As NetworkStream = client.GetStream()

            'Invio un messaggio al server connesso 
            stream.Write(data, 0, data.Length)

            TextBox1.Text += "Inviato: " & message & vbCrLf

            'ricevo la risposta del server e la memorizzo nel buffer
            data = New [Byte](256) {}

           Dim responseData As [String] = [String].Empty

            'Leggo la risposta del server tcp
            Dim bytes As Int32 = stream.Read(data, 0, data.Length)
            responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes)
            TextBox1.Text += "Ricevuto: " & responseData & vbCrLf

            'Chiudo il canale e la connessione tcp
            stream.Close()
            client.Close()

        Catch ex As ArgumentNullException
            TextBox1.Text += "ArgumentNullException: " & ex.Message & vbCrLf
        Catch ex As Net.Sockets.SocketException
            TextBox1.Text += "SocketException: " & ex.Message & vbCrLf
        End Try

    End Sub

    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

        Connect("000.000.00.0", "Ciao")

    End Sub