Option Explicit On 
Option Strict On
 
 
Imports System
Imports System.IO
Imports System.Net
Imports System.Text
Imports System.Net.Sockets
Imports System.Net.Sockets.TcpListener
Imports System.Net.Sockets.TcpClient
Imports System.Threading
 
Public Class Form1
    Inherits System.Windows.Forms.Form
 
" Vom Windows Form Designer generierter Code "
 
 
'das ist die Threadprozedur
Sub Listen()
 
        While True
 
            ' neuen Socket anlegen fuer den Client
            Dim Clientsocket As Socket
 
            'wenn sich ein Client anmeldet
            Clientsocket = server.Accept()
 
            ' Ausgabe 
            Label1.Text = "Client is connected with server"
 
        End While
 
 
End Sub
 
 
    'Variablen definieren
 
    Dim server As New Socket(AddressFamily.InterNetwork, SocketType.Stream, _
      ProtocolType.IP)
 
    Dim ipAdress As IPAddress = ipAdress.Parse("127.0.0.1")
 
    Dim localEP As New IPEndPoint(ipAdress, 13000)
 
    Dim ListenThread As New Threading.Thread(AddressOf Listen)
 
 
 
    Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button1.Click
 
 
        Try
 
            server.Bind(localEP)
 
            Label1.Text = "listen"
 
            server.Listen(1)
 
 
            'anlegen und denn Thread starten
 
            ListenThread.Start()
 
        Catch ex As Exception
            MsgBox(ex.Message, MsgBoxStyle.OKOnly)
 
 
        End Try
 
 
    End Sub
 
    Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As _
      System.EventArgs) Handles Button2.Click
 
        'Thread beenden
        ListenThread.Abort()
 
    End Sub
End Class