VB.Net Tutorial/Socket Network/Socket Server

Date time server based on System.Net.Sockets.Socket

Imports System.Net
Imports System.Net.Sockets
Imports System.Threading
Imports System.Text
Public Class DateTimeServer
  Public Shared Sub Main()
    Dim serverSocket As System.Net.Sockets.Socket
    Try
      Dim hostname As String = Dns.GetHostName()
      Dim serverIP As IPAddress = Dns.Resolve(hostname).AddressList(0)
      Dim Port As String = "13"
      Dim serverhost As New IPEndPoint(serverIP, Int32.Parse(Port))
      serverSocket = New Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp)
      serverSocket.Bind(serverhost)
      serverSocket.Listen(50)
      Console.WriteLine("DateTime server started at: " + serverhost.Address.ToString() + ":" + Port)
      Dim lc As New ListenClient(serverSocket)
      Dim serverthread As New Thread(New ThreadStart(AddressOf lc.ServerThreadProc))
      serverthread.Start()
    Catch ex As Exception
      Console.WriteLine(ex.StackTrace.ToString())
    End Try
  End Sub
End Class

Public Class ListenClient
  Private serverSocket As System.Net.Sockets.Socket

  Public Sub New(ByVal serverSocket As System.Net.Sockets.Socket)
    Me.serverSocket = serverSocket
  End Sub
  Public Sub ServerThreadProc()
    Dim clientSocket As System.Net.Sockets.Socket
    Try
      While (True)
        clientSocket = serverSocket.Accept()
        Dim clientInfo As IPEndPoint = CType( _
            clientSocket.RemoteEndPoint, _
            IPEndPoint)
        Dim serverInfo As IPEndPoint = CType( _
            serverSocket.LocalEndPoint, _
            IPEndPoint)
        Console.WriteLine("Client: " + clientInfo.Address.ToString() + ":" + clientInfo.Port.ToString())
        Console.WriteLine("Server: " + serverInfo.Address.ToString() + ":" + serverInfo.Port.ToString())
        Dim strDate As String = DateTime.Now.ToShortDateString() + " " + DateTime.Now.ToLongTimeString()
        Dim byteDateLine() As Byte = Encoding.ASCII.GetBytes(strDate.ToCharArray())
        clientSocket.Send(byteDateLine, byteDateLine.Length, SocketFlags.None)
        Console.WriteLine("To Client: " + clientInfo.Address.ToString() + ":" + clientInfo.Port.ToString() + ": " + strDate)
        clientSocket.Shutdown(SocketShutdown.Both)
        clientSocket.Close()
      End While
    Catch ex As Exception
      Console.WriteLine(ex.StackTrace.ToString())
      If clientSocket.Connected Then
        clientSocket.Close()
      End If
    End Try
  End Sub
End Class

Socket server

Imports System.Threading
Imports System.Net
Imports System.Net.Sockets

Public Class ServerSocket
  Public Shared Sub Main()
    Try
      Dim serverSocket As New Socket(AddressFamily.InterNetwork,SocketType.Stream,ProtocolType.Tcp)
      Dim serverIP As IPAddress = IPAddress.Parse("127.0.0.1")
      Dim Port As String = "80"
      Dim serverhost As New IPEndPoint(serverIP, Int32.Parse(Port))
      serverSocket.Bind(serverhost)
      serverSocket.Listen(50)
      Console.WriteLine("Server started at: " + serverIP.ToString() + ":" + Port)
      Dim lc As New ListenClient(serverSocket)
      Dim serverthread As New Thread(New ThreadStart(AddressOf lc.ServerThreadProc))
      serverthread.Start()
    Catch ex As Exception
      Console.WriteLine(ex.StackTrace.ToString())
    End Try
  End Sub
End Class

Public Class ListenClient
  Private serverSocket As System.Net.Sockets.Socket
  Private clientSocket As System.Net.Sockets.Socket
  Public Sub New(ByVal serverSocket As System.Net.Sockets.Socket)
    Me.serverSocket = serverSocket
  End Sub
  Public Sub ServerThreadProc()
    Do While True
      Try
        Dim clientSocket As Socket = serverSocket.Accept()
        Dim clientInfo As IPEndPoint = CType( _
            clientSocket.RemoteEndPoint, _
            IPEndPoint)
        Dim serverInfo As IPEndPoint = CType( _
            serverSocket.LocalEndPoint, _
            IPEndPoint)
        Console.WriteLine("Client: " + clientInfo.Address.ToString() + ":" + clientInfo.Port.ToString())
        Console.WriteLine("Server: " + serverInfo.Address.ToString() + ":" + serverInfo.Port.ToString())
      Catch ex As Exception
        Console.WriteLine(ex.StackTrace.ToString())
      End Try
    Loop
  End Sub
End Class

Server started at: 127.0.0.1:80
^CTerminate batch job (Y/N)? n

Socket Server with user interface

Imports System.Text
Imports System.Net.Sockets
Imports System.Threading
Imports System.Windows.Forms
public class SocketServerUI
   public Shared Sub Main
        Application.Run(New Form1)
   End Sub
End class
Public Class Form1
    Inherits System.Windows.Forms.Form
    Public Sub New()
        MyBase.New()
        InitializeComponent()
    End Sub
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
    Private components As System.ruponentModel.IContainer
    Friend WithEvents btnListener As System.Windows.Forms.Button
    Friend WithEvents lblMessage As System.Windows.Forms.Label
    Friend WithEvents lblConnection As System.Windows.Forms.Label
    Friend WithEvents lblPort As System.Windows.Forms.Label
    Friend WithEvents txtPort As System.Windows.Forms.TextBox
    Friend WithEvents btnClose As System.Windows.Forms.Button
    Friend WithEvents txtContent As System.Windows.Forms.TextBox
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents btnWrite As System.Windows.Forms.Button
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.btnListener = New System.Windows.Forms.Button()
        Me.lblMessage = New System.Windows.Forms.Label()
        Me.lblConnection = New System.Windows.Forms.Label()
        Me.lblPort = New System.Windows.Forms.Label()
        Me.txtPort = New System.Windows.Forms.TextBox()
        Me.btnClose = New System.Windows.Forms.Button()
        Me.txtContent = New System.Windows.Forms.TextBox()
        Me.Label1 = New System.Windows.Forms.Label()
        Me.btnWrite = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        "
        "btnListener
        "
        Me.btnListener.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnListener.Location = New System.Drawing.Point(338, 28)
        Me.btnListener.Name = "btnListener"
        Me.btnListener.Size = New System.Drawing.Size(113, 32)
        Me.btnListener.TabIndex = 0
        Me.btnListener.Text = "Start Listening"
        "
        "lblMessage
        "
        Me.lblMessage.BackColor = System.Drawing.Color.White
        Me.lblMessage.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.lblMessage.Location = New System.Drawing.Point(164, 80)
        Me.lblMessage.Name = "lblMessage"
        Me.lblMessage.Size = New System.Drawing.Size(389, 24)
        Me.lblMessage.TabIndex = 1
        "
        "lblConnection
        "
        Me.lblConnection.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.lblConnection.Location = New System.Drawing.Point(61, 80)
        Me.lblConnection.Name = "lblConnection"
        Me.lblConnection.Size = New System.Drawing.Size(93, 24)
        Me.lblConnection.TabIndex = 2
        Me.lblConnection.Text = "Connection Message"
        "
        "lblPort
        "
        Me.lblPort.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.lblPort.Location = New System.Drawing.Point(41, 33)
        Me.lblPort.Name = "lblPort"
        Me.lblPort.Size = New System.Drawing.Size(113, 24)
        Me.lblPort.TabIndex = 3
        Me.lblPort.Text = "Port"
        "
        "txtPort
        "
        Me.txtPort.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.txtPort.Location = New System.Drawing.Point(164, 31)
        Me.txtPort.Name = "txtPort"
        Me.txtPort.Size = New System.Drawing.Size(133, 26)
        Me.txtPort.TabIndex = 4
        Me.txtPort.Text = ""
        "
        "btnClose
        "
        Me.btnClose.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnClose.Location = New System.Drawing.Point(471, 27)
        Me.btnClose.Name = "btnClose"
        Me.btnClose.Size = New System.Drawing.Size(102, 32)
        Me.btnClose.TabIndex = 5
        Me.btnClose.Text = "Stop Connection"
        "
        "txtContent
        "
        Me.txtContent.Location = New System.Drawing.Point(164, 120)
        Me.txtContent.Multiline = True
        Me.txtContent.Name = "txtContent"
        Me.txtContent.Size = New System.Drawing.Size(389, 88)
        Me.txtContent.TabIndex = 6
        Me.txtContent.Text = ""
        "
        "Label1
        "
        Me.Label1.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.Label1.Location = New System.Drawing.Point(61, 120)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(93, 24)
        Me.Label1.TabIndex = 7
        Me.Label1.Text = "Data"
        "
        "btnWrite
        "
        Me.btnWrite.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnWrite.Location = New System.Drawing.Point(573, 120)
        Me.btnWrite.Name = "btnWrite"
        Me.btnWrite.Size = New System.Drawing.Size(123, 32)
        Me.btnWrite.TabIndex = 8
        Me.btnWrite.Text = "Write"
        "
        "Form1
        "
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(716, 261)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.btnWrite, Me.Label1, Me.txtContent, Me.btnClose, Me.txtPort, Me.lblPort, Me.lblConnection, Me.lblMessage, Me.btnListener})
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)
    End Sub

    Dim intPort As Integer
    Dim myTcpListener As TcpListener
    Dim myNetworkStream As NetworkStream
    Private Sub btnListener_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnListener.Click
        Dim myThread As New Thread(New ThreadStart(AddressOf StartListen))
        myThread.Start()
    End Sub
    Private Sub StartListen()
        intPort = Integer.Parse(txtPort.Text)
        myTcpListener = New TcpListener(intPort)
        Dim blnConection As Boolean = False
        Try
            myTcpListener.Start()
            lblMessage.Text = "Waiting..."
            Dim mySocket As Socket = myTcpListener.AcceptSocket()

            Do
                If mySocket.Connected = True Then
                    lblMessage.Text = "Port: " + txtPort.Text + "Connected"
                    myNetworkStream = New NetworkStream(mySocket)
                    Dim strContent As String
                    Dim lngByte As Long = myNetworkStream.ReadByte()
                    Dim myByte(lngByte) As Byte
                    myNetworkStream.Read(myByte, 0, lngByte)
                    strContent = Encoding.ASCII.GetString(myByte, 0, lngByte)
                    txtContent.Text = strContent
                End If
            Loop
        Catch ex As SocketException
            MessageBox.Show _
            (ex.Message, "Connection Error", MessageBoxButtons.OK, MessageBoxIcon.Warning)
        End Try
    End Sub
    Private Sub btnClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.Click
        myTcpListener.Stop()
    End Sub
    Private Sub btnWrite_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnWrite.Click
       
        Dim strTest As String = txtContent.Text
        Dim myBytes() As Byte = Encoding.ASCII.GetBytes(strTest)
        lblMessage.Text = ("Message")
        myNetworkStream.Write(myBytes, 0, myBytes.Length)
    End Sub
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    End Sub
End Class

Using Async Socket Server

Imports System.Net.Sockets
Imports System.Net
Imports System.Threading
Imports System.Text
Imports System.Windows.Forms
public class UsingAsyncSocketServer
   public Shared Sub Main
        Application.Run(New Form1)
   End Sub
End class
Public Class Form1
    Inherits System.Windows.Forms.Form
    Public Sub New()
        MyBase.New()
        InitializeComponent()
    End Sub
    Protected Overloads Overrides Sub Dispose(ByVal disposing As Boolean)
        If disposing Then
            If Not (components Is Nothing) Then
                components.Dispose()
            End If
        End If
        MyBase.Dispose(disposing)
    End Sub
    Private components As System.ruponentModel.IContainer
    Friend WithEvents btnListener As System.Windows.Forms.Button
    Friend WithEvents lblConnection As System.Windows.Forms.Label
    Friend WithEvents lblPort As System.Windows.Forms.Label
    Friend WithEvents txtPort As System.Windows.Forms.TextBox
    Friend WithEvents btnClose As System.Windows.Forms.Button
    Friend WithEvents btnReceive As System.Windows.Forms.Button
    Friend WithEvents txtMessage As System.Windows.Forms.TextBox
    Friend WithEvents Label1 As System.Windows.Forms.Label
    Friend WithEvents btnSend As System.Windows.Forms.Button
    Friend WithEvents txtAccept As System.Windows.Forms.TextBox
    <System.Diagnostics.DebuggerStepThrough()> Private Sub InitializeComponent()
        Me.btnListener = New System.Windows.Forms.Button()
        Me.lblConnection = New System.Windows.Forms.Label()
        Me.lblPort = New System.Windows.Forms.Label()
        Me.txtPort = New System.Windows.Forms.TextBox()
        Me.btnClose = New System.Windows.Forms.Button()
        Me.btnReceive = New System.Windows.Forms.Button()
        Me.txtMessage = New System.Windows.Forms.TextBox()
        Me.txtAccept = New System.Windows.Forms.TextBox()
        Me.Label1 = New System.Windows.Forms.Label()
        Me.btnSend = New System.Windows.Forms.Button()
        Me.SuspendLayout()
        "
        "btnListener
        "
        Me.btnListener.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnListener.Location = New System.Drawing.Point(338, 24)
        Me.btnListener.Name = "btnListener"
        Me.btnListener.Size = New System.Drawing.Size(113, 32)
        Me.btnListener.TabIndex = 0
        Me.btnListener.Text = "Start"
        "
        "lblConnection
        "
        Me.lblConnection.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.lblConnection.Location = New System.Drawing.Point(41, 72)
        Me.lblConnection.Name = "lblConnection"
        Me.lblConnection.Size = New System.Drawing.Size(92, 24)
        Me.lblConnection.TabIndex = 2
        Me.lblConnection.Text = "Info"
        "
        "lblPort
        "
        Me.lblPort.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.lblPort.Location = New System.Drawing.Point(20, 32)
        Me.lblPort.Name = "lblPort"
        Me.lblPort.Size = New System.Drawing.Size(113, 24)
        Me.lblPort.TabIndex = 3
        Me.lblPort.Text = "Port"
        "
        "txtPort
        "
        Me.txtPort.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.txtPort.Location = New System.Drawing.Point(143, 24)
        Me.txtPort.Name = "txtPort"
        Me.txtPort.Size = New System.Drawing.Size(133, 26)
        Me.txtPort.TabIndex = 4
        Me.txtPort.Text = "36000"
        "
        "btnClose
        "
        Me.btnClose.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnClose.Location = New System.Drawing.Point(461, 24)
        Me.btnClose.Name = "btnClose"
        Me.btnClose.Size = New System.Drawing.Size(102, 32)
        Me.btnClose.TabIndex = 5
        Me.btnClose.Text = "Stop"
        "
        "btnReceive
        "
        Me.btnReceive.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnReceive.Location = New System.Drawing.Point(276, 248)
        Me.btnReceive.Name = "btnReceive"
        Me.btnReceive.Size = New System.Drawing.Size(175, 32)
        Me.btnReceive.TabIndex = 6
        Me.btnReceive.Text = "Receive"
        "
        "txtMessage
        "
        Me.txtMessage.Location = New System.Drawing.Point(143, 72)
        Me.txtMessage.Multiline = True
        Me.txtMessage.Name = "txtMessage"
        Me.txtMessage.ScrollBars = System.Windows.Forms.ScrollBars.Vertical
        Me.txtMessage.Size = New System.Drawing.Size(430, 88)
        Me.txtMessage.TabIndex = 7
        Me.txtMessage.Text = ""
        "
        "txtAccept
        "
        Me.txtAccept.Location = New System.Drawing.Point(143, 168)
        Me.txtAccept.Multiline = True
        Me.txtAccept.Name = "txtAccept"
        Me.txtAccept.ScrollBars = System.Windows.Forms.ScrollBars.Vertical
        Me.txtAccept.Size = New System.Drawing.Size(430, 64)
        Me.txtAccept.TabIndex = 9
        Me.txtAccept.Text = ""
        "
        "Label1
        "
        Me.Label1.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.Label1.Location = New System.Drawing.Point(10, 168)
        Me.Label1.Name = "Label1"
        Me.Label1.Size = New System.Drawing.Size(144, 24)
        Me.Label1.TabIndex = 8
        Me.Label1.Text = "Data"
        "
        "btnSend
        "
        Me.btnSend.Font = New System.Drawing.Font("Microsoft Sans Serif", 12.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(136, Byte))
        Me.btnSend.Location = New System.Drawing.Point(461, 248)
        Me.btnSend.Name = "btnSend"
        Me.btnSend.Size = New System.Drawing.Size(112, 32)
        Me.btnSend.TabIndex = 10
        Me.btnSend.Text = "Data sent back"
        "
        "Form1
        "
        Me.AutoScaleBaseSize = New System.Drawing.Size(6, 14)
        Me.ClientSize = New System.Drawing.Size(665, 309)
        Me.Controls.AddRange(New System.Windows.Forms.Control() {Me.btnSend, Me.txtAccept, Me.Label1, Me.txtMessage, Me.btnReceive, Me.btnClose, Me.txtPort, Me.lblPort, Me.lblConnection, Me.btnListener})
        Me.Name = "Form1"
        Me.Text = "Form1"
        Me.ResumeLayout(False)
    End Sub
    Dim strMessage
    Dim myListener As Socket
    Dim bteAccept(65536) As Byte
    Dim bteSend(65536) As Byte
    Dim EndSocket As Socket
    Private Sub btnListener_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnListener.Click
        Dim myThread As New Thread(New ThreadStart(AddressOf StartListen))
        myThread.Start()
    End Sub
    Private Sub btnReceive_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnReceive.Click
        Dim myThread As New Thread(New ThreadStart(AddressOf ReceiveStart))
        myThread.Start()
    End Sub
    Private Sub btnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnSend.Click
        Dim myThread As New Thread(New ThreadStart(AddressOf SendStart))
        myThread.Start()
    End Sub

    Private Sub StartListen()
        Dim intPort As Integer
        Dim bidEndPoint As IPEndPoint
        intPort = Integer.Parse(txtPort.Text)
        bidEndPoint = New IPEndPoint(IPAddress.Parse("10.2.3.127"), intPort)
        myListener = New Socket _
                     (AddressFamily.InterNetwork, _
                     SocketType.Stream, _
                     ProtocolType.Tcp)
        Try
            "  myListener.Bind(bidEndPoint)
            Dim myAsyncCallBack As New AsyncCallback(AddressOf AcceptEnd)
            myListener.Listen(intPort)
            myListener.BeginAccept(myAsyncCallBack, myListener)
            txtMessage.Text += vbCrLf + "Waiting"
            strMessage += "//Head..." + vbCrLf
            strMessage += "//Server Send Message ..." + vbCrLf
            strMessage += "--------------------------------" + vbCrLf

        Catch ex As SocketException
            Console.WriteLine(ex.Message)
        End Try
    End Sub
    Private Sub AcceptEnd(ByVal pIAsyncResult As IAsyncResult)
        EndSocket = myListener.EndAccept(pIAsyncResult)
    End Sub
    Private Sub ReceiveStart()
        Dim myAsyncCallBack As New AsyncCallback(AddressOf ReceiveData)
        EndSocket.BeginReceive _
          (bteAccept, 0, 65536, 0, _
          myAsyncCallBack, EndSocket)
    End Sub
    Private Sub ReceiveData(ByVal pIAsyncResult As IAsyncResult)
        Dim intByte As Integer
        intByte = EndSocket.EndReceive(pIAsyncResult)
        If intByte > 0 Then
            strMessage += Encoding.ASCII.GetString(bteAccept)
            txtAccept.Text = strMessage
        End If
    End Sub
    Private Sub SendStart()
        Dim myAsyncCallBack As New AsyncCallback(AddressOf SendData)
        bteSend = Encoding.ASCII.GetBytes(strMessage)
        EndSocket.BeginSend _
          (bteSend, 0, bteSend.Length, _
          SocketFlags.DontRoute, myAsyncCallBack, EndSocket)
    End Sub
    Private Sub SendData(ByVal pIAsyncResult As IAsyncResult)
        Dim intSend As Integer
        intSend = EndSocket.EndSend(pIAsyncResult)
        txtMessage.Text += vbCrLf + "Data sent " + intSend.ToString + "bytes"
    End Sub
    Private Sub btnClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.Click
        myListener.Close()
    End Sub

    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    End Sub
End Class