Imports System

Imports System.IO

Imports System.Net

Imports System.Net.Sockets

Imports System.Text

Imports Microsoft.VisualBasic

Module Module1

    Sub Main()

        Dim server As TcpListener

        server = Nothing

        Try

            Dim port As Int32 = 13000

            Dim localAddr As IPAddress = IPAddress.Parse("192.168.0.198")

            server = New TcpListener(localAddr, port)

            server.Start()

            Dim bytes(1024) As Byte

            Dim data As String = Nothing

            While True

                Console.Write("Waiting for a connection... ")

                Dim client As TcpClient = server.AcceptTcpClient()

                Console.WriteLine("Connected!")

                data = Nothing

                Dim stream As NetworkStream = client.GetStream()

                Dim i As Int32

                i = stream.Read(bytes, 0, bytes.Length)

                While (i <> 0)

                    data = System.Text.Encoding.ASCII.GetString(bytes, 0, i)

                    Console.WriteLine("Received: {0}", data)

                    data = data.ToUpper()

                    Dim msg As Byte() = System.Text.Encoding.ASCII.GetBytes(data)

                    stream.Write(msg, 0, msg.Length)

                    Console.WriteLine("Sent: {0}", data)

                    i = stream.Read(bytes, 0, bytes.Length)

                End While

                client.Close()

            End While

        Catch e As SocketException

            Console.WriteLine("SocketException: {0}", e)

        Finally

            server.Stop()

        End Try

        Console.WriteLine(ControlChars.Cr + "Hit enter to continue....")

        Console.Read()

    End Sub

End Module

Imports System

Imports System.IO

Imports System.Net

Imports System.Net.Sockets

Imports System.Text

Imports Microsoft.VisualBasic

Module Module1

    Sub Main()

        Dim server As TcpListener

        server = Nothing

        Try

            Dim port As Int32 = 15000

            Dim localAddr As IPAddress = IPAddress.Parse("192.168.0.198")

            server = New TcpListener(localAddr, port)

            server.Start()

            Dim bytes(1024) As Byte

            Dim data As String = Nothing

            While True

                Console.Write("Waiting for a connection... ")

                Dim client As TcpClient = server.AcceptTcpClient()

                Console.WriteLine("Connected!")

                data = Nothing

                Dim stream As NetworkStream = client.GetStream()

                Dim i As Int32

                i = stream.Read(bytes, 0, bytes.Length)

                While (i <> 0)

                    data = System.Text.Encoding.ASCII.GetString(bytes, 0, i)

                    Console.WriteLine("Received: {0}", data)

                    data = data.ToUpper()

                    Dim msg As Byte() = System.Text.Encoding.ASCII.GetBytes(data)

                    stream.Write(msg, 0, msg.Length)

                    Console.WriteLine("Sent: {0}", data)

                    i = stream.Read(bytes, 0, bytes.Length)

                End While

                client.Close()

            End While

        Catch e As SocketException

            Console.WriteLine("SocketException: {0}", e)

        Finally

            server.Stop()

        End Try

        Console.WriteLine(ControlChars.Cr + "Hit enter to continue....")

        Console.Read()

    End Sub

End Module

Imports System

Imports System.IO

Imports System.Net

Imports System.Net.Sockets

Imports System.Text

Imports Microsoft.VisualBasic

Module Module1

    Sub Main()

        Connect("192.168.0.198", "123")

    End Sub

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

        Try

            Dim port As Int32 = 13000

            Dim client As New TcpClient(server, port)

            Dim data As [Byte]() = System.Text.Encoding.ASCII.GetBytes(message)

            Dim stream As NetworkStream = client.GetStream()

            stream.Write(data, 0, data.Length)

            Console.WriteLine("Sent: {0}", message)

            data = New [Byte](256) {}

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

            Dim bytes As Int32 = stream.Read(data, 0, data.Length)

            responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes)

            Console.WriteLine("Received: {0}", responseData)

            stream.Close()

            client.Close()

        Catch e As ArgumentNullException

            Console.WriteLine("ArgumentNullException: {0}", e)

        Catch e As SocketException

            Console.WriteLine("SocketException: {0}", e)

        End Try

        Console.WriteLine(ControlChars.Cr + " Press Enter to continue...")

        Console.Read()

    End Sub 'Connect

End Module