[02/03] help creating a messenger

[sheikh78]

And this also from the MSDN article for the chat client:

Imports System
Imports System.Net
Imports System.Net.Sockets
Imports System.Threading
Imports System.Text
 
' State object for receiving data from remote device.
Public Class StateObject
    ' Client socket.
    Public workSocket As Socket = Nothing
    ' Size of receive buffer.
    Public BufferSize As Integer = 256
    ' Receive buffer.
    Public buffer(256) As Byte
    ' Received data string.
    Public sb As New StringBuilder()
End Class 'StateObject
 
Public Class AsynchronousClient
    ' The port number for the remote device.
    Private Shared port As Integer = 8000
 
    ' ManualResetEvent instances signal completion.
    Private Shared connectDone As New ManualResetEvent(False)
    Private Shared sendDone As New ManualResetEvent(False)
    Private Shared receiveDone As New ManualResetEvent(False)
 
    ' The response from the remote device.
    Private Shared response As [String] = [String].Empty
 
 
    Private Shared Sub StartClient()
        ' Connect to a remote device.
        Try
            ' Establish the remote endpoint for the socket.
            ' The name of the
            ' remote device is "host.contoso.com".
            Dim ipHostInfo As IPHostEntry = Dns.GetHostEntry("127.0.0.1")
            Dim ipAddress As IPAddress = ipHostInfo.AddressList(0)
            Dim remoteEP As New IPEndPoint(ipAddress, port)
 
            '  Create a TCP/IP socket.
            Dim client As New Socket(AddressFamily.InterNetwork, _
                SocketType.Stream, ProtocolType.Tcp)
 
            ' Connect to the remote endpoint.
            client.BeginConnect(remoteEP, AddressOf ConnectCallback, client)
            connectDone.WaitOne()
 
            ' Send test data to the remote device.
            Send(client, "This is a test<EOF>")
            sendDone.WaitOne()
 
            ' Receive the response from the remote device.
            Receive(client)
            receiveDone.WaitOne()
 
            ' Write the response to the console.
            Console.WriteLine("Response received : {0}", response)
 
            ' Release the socket.
            client.Shutdown(SocketShutdown.Both)
            client.Close()
 
        Catch e As Exception
            Console.WriteLine(e.ToString())
        End Try
    End Sub 'StartClient
 
 
    Private Shared Sub ConnectCallback(ByVal ar As IAsyncResult)
        Try
            ' Retrieve the socket from the state object.
            Dim client As Socket = CType(ar.AsyncState, Socket)
 
            ' Complete the connection.
            client.EndConnect(ar)
 
            Console.WriteLine("Socket connected to {0}", _
                client.RemoteEndPoint.ToString())
 
            ' Signal that the connection has been made.
            connectDone.Set()
        Catch e As Exception
            Console.WriteLine(e.ToString())
        End Try
    End Sub 'ConnectCallback
 
 
    Private Shared Sub Receive(ByVal client As Socket)
        Try
            ' Create the state object.
            Dim state As New StateObject()
            state.workSocket = client
 
            ' Begin receiving the data from the remote device.
            client.BeginReceive(state.buffer, 0, state.BufferSize, 0, _
                AddressOf ReceiveCallback, state)
        Catch e As Exception
            Console.WriteLine(e.ToString())
        End Try
    End Sub 'Receive
 
 
    Private Shared Sub ReceiveCallback(ByVal ar As IAsyncResult)
        Try
            ' Retrieve the state object and client socket 
            ' from the asynchronous state object.
            Dim state As StateObject = CType(ar.AsyncState, StateObject)
            Dim client As Socket = state.workSocket
 
            ' Read data from the remote device.
            Dim bytesRead As Integer = client.EndReceive(ar)
 
            If bytesRead > 0 Then
                ' There might be more data, so store the data received so far.
                state.sb.Append(Encoding.ASCII.GetString(state.buffer, 0, _
                    bytesRead))
 
                ' Get the rest of the data.
                client.BeginReceive(state.buffer, 0, state.BufferSize, 0, _
                    AddressOf ReceiveCallback, state)
            Else
                ' All the data has arrived; put it in response.
                If state.sb.Length > 1 Then
                    response = state.sb.ToString()
                End If
                ' Signal that all bytes have been received.
                receiveDone.Set()
            End If
        Catch e As Exception
            Console.WriteLine(e.ToString())
        End Try
    End Sub 'ReceiveCallback
 
 
    Private Shared Sub Send(ByVal client As Socket, ByVal data As [String])
        ' Convert the string data to byte data using ASCII encoding.
        Dim byteData As Byte() = Encoding.ASCII.GetBytes(data)
 
        ' Begin sending the data to the remote device.
        client.BeginSend(byteData, 0, byteData.Length, 0, _
            AddressOf SendCallback, client)
    End Sub 'Send
 
 
    Private Shared Sub SendCallback(ByVal ar As IAsyncResult)
        Try
            ' Retrieve the socket from the state object.
            Dim client As Socket = CType(ar.AsyncState, Socket)
 
            ' Complete sending the data to the remote device.
            Dim bytesSent As Integer = client.EndSend(ar)
            Console.WriteLine("Sent {0} bytes to server.", bytesSent)
 
            ' Signal that all bytes have been sent.
            sendDone.Set()
        Catch e As Exception
            Console.WriteLine(e.ToString())
        End Try
    End Sub 'SendCallback
 
    'Entry point that delegates to C-style main Private Function.
    Private Overloads Shared Sub Main()
        System.Environment.ExitCode = _
           Main(System.Environment.GetCommandLineArgs())
    End Sub
 
 
    Public Overloads Shared Function Main(ByVal args() As [String]) As Integer
        StartClient()
        Return 0
    End Function 'Main
End Class 'AsynchronousClient

Help? The client keep saying: "System.Net.Sockets.SocketException: No connection could be made because the target machine actively refused it." But if you look at the code it doesn't refuse it.