Imports System.Text
Imports System.Net.Sockets
 
Public Class Server
 
    Dim Data As Integer
    Dim Message As String
 
    Dim TCPL As TcpListener
    Dim TCPC As New TcpClient
 
    Dim BufferSize(TCPC.ReceiveBufferSize - 1) As Byte
 
    Private Sub Server_Load(ByVal sender As System.Object, _
        ByVal e As System.EventArgs) Handles MyBase.Load
        'Always set to true
        Me.BackgroundWorker1.WorkerReportsProgress = True
 
        Try
            TCPL = New TcpListener(Net.IPAddress.Any, 13636)
            TCPL.Start()
            ListBox1.Items.Add("Waiting for connection...")
 
            TCPL.BeginAcceptTcpClient(AddressOf OnConnect, Nothing)
        Catch ex As Exception
            ListBox1.Items.Add("Error: " & ex.Message)
        End Try
    End Sub
 
    Private Sub OnConnect(ByVal AR As IAsyncResult)
        TCPC = TCPL.EndAcceptTcpClient(AR)
 
        Me.BackgroundWorker1.RunWorkerAsync("Connection with client has " & _
            "been established!")
 
        TCPC.GetStream.BeginRead(BufferSize, 0, BufferSize.Length, AddressOf _
          OnRead, _
            Nothing)
    End Sub
 
    Private Sub OnRead(ByVal AR As IAsyncResult)
        Data = TCPC.GetStream.EndRead(AR)
 
        Message = Encoding.ASCII.GetString(BufferSize, 0, Data)
 
        Me.BackgroundWorker1.RunWorkerAsync(Message)
 
        TCPC.GetStream.BeginRead(BufferSize, 0, BufferSize.Length, AddressOf _
          OnRead, _
            Nothing)
    End Sub
 
#Region " Background Worker "
    Private Sub BackgroundWorker1_DoWork(ByVal sender As Object, _
            ByVal e As System.ComponentModel.DoWorkEventArgs) _
                Handles BackgroundWorker1.DoWork
        Me.BackgroundWorker1.ReportProgress(100, e.Argument)
    End Sub
 
    Private Sub BackgroundWorker1_ProgressChanged(ByVal sender As Object, _
        ByVal e As System.ComponentModel.ProgressChangedEventArgs) _
            Handles BackgroundWorker1.ProgressChanged
        ListBox1.Items.Add(e.UserState)
    End Sub
#End Region
End Class