[RESOLVED] [2005] TCPListener, Threading, Error.

I have been grabbing code from all over, including this post.

http://www.vbforums.com/showthread.php?t=451368

I used a working console code for a client from http://www.eggheadcafe.com/articles/20020323.asp

But my code below is not accepting the connection.
The code from eggheadcafe works with the server code from eggheadcafe. So I know I did something wrong in my code for my windows application.

The complete error message is

Code:

---

System.Net.Sockets.SocketException was unhandled
  ErrorCode=10061
  Message="No connection could be made because the target machine actively refused it"
  Source="System"
  StackTrace:
      at System.Net.Sockets.TcpClient.Connect(String hostname, Int32 port)
      at TCP___CLient.TCPCli.Main() in C:\Documents and Settings\Owner\Local Settings\Application Data\Temporary Projects\TCP - CLient\Module1.vb:line 7
      at System.AppDomain.nExecuteAssembly(Assembly assembly, String[] args)
      at System.AppDomain.ExecuteAssembly(String assemblyFile, Evidence assemblySecurity, String[] args)
      at Microsoft.VisualStudio.HostingProcess.HostProc.RunUsersAssembly()
      at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
      at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
      at System.Threading.ThreadHelper.ThreadStart()

---

vb Code:

Public Class Form1
    Dim listeners(9) As Net.Sockets.TcpListener
    Dim thrListen As New Threading.Thread(AddressOf DoListen)
 
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
 
        For i As Integer = 0 To 9
            listeners(i).Stop()
            listeners(i) = Nothing
        Next
        thrListen.Abort()
 
    End Sub
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim basePort As Integer = 44000
        For i As Integer = 0 To 9
            listeners(i) = New Net.Sockets.TcpListener(Net.IPAddress.Any, basePort + i)
        Next
 
        thrListen.Start()
 
    End Sub
    Private Sub DoListen()
        Dim client As Net.Sockets.TcpClient
        Dim sr As IO.StreamReader
        Do
            For i As Integer = 0 To 9
                Try
                    client = listeners(i).AcceptTcpClient
                    MsgBox("A")
                    sr = New IO.StreamReader(client.GetStream)
                    MessageBox.Show("TcpListener " & i.ToString & " recieved the following:" & Environment.NewLine & sr.ReadToEnd)
 
                Catch
 
                End Try
            Next
        Loop
    End Sub
 
End Class

Just wondering if anyone had any idea's? Still new to vb2005, I migrated from VB6 recently.

[edit]

I found part of the problem.
the Try Catch was skipping over an error, the error said you must start the event first.
I added
listeners(i).start()

the client connected, but the data was never accepted/sent. I'll play with it some more.

I'll look into your problem tomorrow. Sleeping time now:)

I think I may have figured out more of the puzzle. It looks like the Client application is sending an array of bytes, and the server applicaiton is trying to receive a string. I don't know if this has anything to do with it or not.

[edit]

here is the client app part from the eggheadcafe website that is sending the data.

vb Code:

Dim tcpClient As New System.Net.Sockets.TcpClient()
        tcpClient.Connect("192.168.1.100", 45000)
        Dim networkStream As NetworkStream = tcpClient.GetStream()
            ' Do a simple write.
            Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes("Is anybody there")
            networkStream.Write(sendBytes, 0, sendBytes.Length)

Ok, I wrote a client and server (Sender and receiver) I am still not getting the data from one app to the other correctly. I get 97, which does correspond to the ascii code value for lower case 'a' but, I have to close the stream, then close the connection before it will work. Is this how I am suppose to be sending information? Request connection, send data, close stream, close connection... For every single message? Even if I want someone to be connected, and be sending data back and forth?

This is my Server.

vb Code:

Imports System.Net.Sockets
Imports System.Text
 
Public Class Form1
    Dim listeners(9) As Net.Sockets.TcpListener
 
    Dim thrListen As New Threading.Thread(AddressOf DoListen)
 
    Private Sub Form1_FormClosing(ByVal sender As Object, ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
 
        For i As Integer = 0 To 9
            listeners(i).Stop()
            listeners(i) = Nothing
        Next
        thrListen.Abort()
 
    End Sub
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim basePort As Integer = 44600
        For i As Integer = 0 To 9
            listeners(i) = New Net.Sockets.TcpListener(Net.IPAddress.Any, basePort + i)
        Next
 
        thrListen.Start()
 
    End Sub
    Private Sub DoListen()
        Dim client As Net.Sockets.TcpClient
        Dim TempString As String
 
        TempString = ""
        Dim sr As IO.StreamReader
        Do
            For i As Integer = 0 To 9
 
                Try
 
                    listeners(i).Start()
 
                    client = listeners(i).AcceptTcpClient
                    sr = New IO.StreamReader(client.GetStream)
 
                    TempString = sr.Read
 
                    MsgBox("TcpListener " & i & " recieved the following:" & vbNewLine & TempString)
 
                Catch
                    MsgBox(Err.Description)
                End Try
            Next
        Loop
    End Sub
End Class

This is my Client.

vb Code:

Imports System.Net.Sockets
Imports System.Text
Public Class Form1
 
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim client As Net.Sockets.TcpClient
        Dim sw As IO.StreamWriter
        client = New Net.Sockets.TcpClient
 
        Try
            client.Connect("192.168.1.100", 44600)
            sw = New IO.StreamWriter(client.GetStream)
            sw.Write("a")
            sw.Close()
            client.Close()
        Catch
            MsgBox(Err.Description)
        End Try
    End Sub
End Class

I just wrote a udp listener the other day, and to avoid this problem I used a background worker, and inside that thread was an infinite loop which done the listening, if I received some bytes, I would pass them in the report progress event, and handled decoding the bytes there, I just always sent 0 for progress and Bytes() as the userstate object param. It worked perfectly, and is quite simple with no need to worry about delegates and invoking other controls...

I will upload it tomorrow if you want, all it does is send bytes to local host, and receives them in the BGworker, the host and listener are in the same class as to make it more readable, and it uses a library called TinyUDP for the host...

Anything will help, dunno how different the coding is for UDP and TCP. Also I just noticed I had some werid bit of dislexia when I wrote the title to this, I have now changed it to TCP instead of LCP, haha.

Should I be using

vb Code:

Dim client As Net.Sockets.TcpClient
client = listeners(i).AcceptTcpClient
 
Dim NWS As System.Net.Sockets.NetworkStream
NWS=Listeners(i).GetStream

instead of

vb Code:

Dim client As Net.Sockets.TcpClient
client = listeners(i).AcceptTcpClient
 
Dim sw As IO.StreamWriter
sw = New IO.StreamWriter(client.GetStream)

Ok, I got the listener to work, but I have a few final questions. If anyone knows please could you answer. I haven't really gotten many responces to this thread.

For some reason when I send data into the datastream, if I use the .write command on the networkstream, 3 different times, my listener will read it all in one time, instead of reading it three different times as three different messeges. Do I have to call a read after a Write?

I don't think it matters which way I went about getting information from the stream, the key was to read and write both in bytes.

Below is the code from the Server (tcpListener)

The following are the text boxes, and there purposes.
TxtChat - This is the chat window/box.
TxtPort - This is the TCP/IP port address to listen on.
TxtUserList - This is the textbox that shows which users have logged in.
TxtMessege - This is where the user will type the messege to send to the others.

The following are the two buttons, and there purposes.
BtnSend - Button that the user clicks to send a messege contained in the txtmessege textbox to the other user.
BtnListen - This button starts the listening (server) interface.

vb Code:

Imports System.Net.Sockets
Imports System.Text
Public Class Form1
    Dim thrListen As New Threading.Thread(AddressOf DoListen)
    Dim MyDataStream As System.Net.Sockets.NetworkStream
    Dim Client As Net.Sockets.TcpClient
    Dim tstServer As Net.Sockets.TcpListener
 
    ' This delegate enables asynchronous calls for setting
    ' the text property on a TextBox control.
    Delegate Sub SetTextCallback(ByVal [text] As String)
 
    Private Sub Form1_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Leave
        MyDataStream.Close()
        tstServer.Stop()
        thrListen.Abort()
    End Sub
    Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 
    End Sub
 
    Private Sub BtnListen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnListen.Click
        tstServer = New Net.Sockets.TcpListener(Net.IPAddress.Any, Int(Val(TxtPort.Text)))
        thrListen.IsBackground = True
        thrListen.Start()
    End Sub
    Private Sub DoListen()
        Dim TempString As String
        TempString = ""
        Do
            Try
                'start the listening
                tstServer.Start()
                'Accept the pending client connection and return             
                'a TcpClient initialized for communication. 
                Client = tstServer.AcceptTcpClient
                'client.
                Me.SetText("Connection Accepted:" & vbNewLine)
                ' Get the stream
                MyDataStream = Client.GetStream
                ' Read the stream into a byte array
                Dim bytes(Client.ReceiveBufferSize) As Byte
                MyDataStream.Read(bytes, 0, CInt(Client.ReceiveBufferSize))
                ' Return the data received from the client to the txtchat textbox.
                TempString = Encoding.ASCII.GetString(bytes)
                Me.SetText(TempString)
                Me.SetText(vbNewLine)
            Catch
                MsgBox(Err.Description)
            End Try
        Loop
    End Sub
 
 
    ' This method demonstrates a pattern for making thread-safe
    ' calls on a Windows Forms control. 
    '
    ' If the calling thread is different from the thread that
    ' created the TextBox control, this method creates a
    ' SetTextCallback and calls itself asynchronously using the
    ' Invoke method.
    '
    ' If the calling thread is the same as the thread that created
    ' the TextBox control, the Text property is set directly. 
 
    Private Sub SetText(ByVal [text] As String)
 
        ' InvokeRequired required compares the thread ID of the
        ' calling thread to the thread ID of the creating thread.
        ' If these threads are different, it returns true.
        If Me.TxtChat.InvokeRequired Then
            Dim d As New SetTextCallback(AddressOf SetText)
            Me.Invoke(d, New Object() {[text]})
        Else
            'Me.TxtChat.Text = Me.TxtChat.Text & [text]
            CheckMessege([text])
        End If
    End Sub
 
    Private Sub BtnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnSend.Click
        If Client.Connected = True Then
            If MyDataStream.CanWrite Then
                Try
                    ' Do a simple write.
                    Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(TxtMessege.Text)
                    MyDataStream.Write(sendBytes, 0, sendBytes.Length)
                    'add the text to the local text box window
                    TxtChat.Text = TxtChat.Text & TxtMessege.Text
                    'clear the user messege that was typed
                    TxtMessege.Text = ""
                Catch
                    MsgBox(Err.Description)
                End Try
            End If
        Else
            TxtChat.Text = TxtChat.Text & "No Client is connected." & vbNewLine
        End If
    End Sub
    Private Sub CheckMessege(ByVal [text] As String)
        MsgBox([text])
        Dim TempMessege() As String
        TempMessege = Split([text], "|-|")
        Select Case TempMessege(0)
            Case "Messege:"
                TxtChat.Text = TxtChat.Text & TempMessege(2) & ": " & TempMessege(1) & vbNewLine
            Case "NewUser:"
                TxtUserList.Text = TxtUserList.Text & TempMessege(2) & vbNewLine
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " Connected"
            Case "Disconnect:"
                TxtUserList.Text.Replace(TempMessege(2) & vbNewLine, "")
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " Disconnected"
            Case "Connect:"
 
            Case Else
 
        End Select
    End Sub
End Class

Sorry, no help from my side, because I seem to have a related problem. In your last post you stated that you send 3 messages and they get recieved as one, are you sending from a client and when is the message been displayed (is the connection still open).
My listener will not display the messages sent by a client until the client closes the connection????

Do you do those 3 .write commands using 3 separate button-clicks or are you doing it by code (which would be faster). In the last case it sounds like the "normal" operation I 've seen using VB6 Winsock for a TCP connection. I had to parse each message since I had multiple occasions when several messages where received a one message. At least you got the messages!

|-| is what I use to "split" the data". I figured just one character might be too easy for someone to accidently type.

I send three .write commands by code. In the code below, I tried doing a .Write, then .Read, then .Write, then .Read.

The messege from the CLient "NewUser:|-||-|Jeremy" is sent, and received.
The messege from the Server "RCVD" is sent, and received by the client.
The remaining messeges from the Client are never received by the server. It's as if the program just skips over them.

Posting the Client that sends the data. And the updated Listener (server)

CLIENT

vb Code:

Imports System.Net.Sockets
Imports System.Text
Class TCPCli
    Shared Sub Main()
 
        Dim tcpClient As New System.Net.Sockets.TcpClient()
        tcpClient.Connect("192.168.1.100", 45000)
        Dim networkStream As NetworkStream = tcpClient.GetStream()
        If networkStream.CanWrite And networkStream.CanRead Then
            ' Do a simple write.
            Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes("NewUser:|-||-|Jeremy")
            networkStream.Write(sendBytes, 0, sendBytes.Length)
 
            Dim bytes2(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes2, 0, CInt(tcpClient.ReceiveBufferSize))
            Dim returndata2 As String = Encoding.ASCII.GetString(bytes2)
            Console.WriteLine(("Data was:" + returndata2))
 
            Dim sendBytes2 As [Byte]() = Encoding.ASCII.GetBytes("Messege:|-|Whats going on?|-|BoB")
            networkStream.Write(sendBytes2, 0, sendBytes2.Length)
 
  
            ' Read the NetworkStream into a byte buffer.
            Dim bytes(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes, 0, CInt(tcpClient.ReceiveBufferSize))
            ' Output the data received from the host to the console.
            Dim returndata As String = Encoding.ASCII.GetString(bytes)
            Console.WriteLine(("Host returned: " + returndata))
            Dim sendBytes3 As [Byte]() = Encoding.ASCII.GetBytes("Disconnect:|-||-|Timmay")
            networkStream.Write(sendBytes3, 0, sendBytes3.Length)
            Dim bytes3(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes3, 0, CInt(tcpClient.ReceiveBufferSize))
 
        Else
            If Not networkStream.CanRead Then
                Console.WriteLine("cannot not write data to this stream")
                tcpClient.Close()
            Else
                If Not networkStream.CanWrite Then
                    Console.WriteLine("cannot read data from this stream")
                    tcpClient.Close()
                End If
            End If
        End If
        ' pause so user can view the console output
        Console.ReadLine()
    End Sub
End Class

---SERVER-------------------------------------

vb Code:

Imports System.Net.Sockets
Imports System.Text
Public Class Form1
    Dim thrListen As New Threading.Thread(AddressOf DoListen)
    Dim MyDataStream As System.Net.Sockets.NetworkStream
    Dim Client As Net.Sockets.TcpClient
    Dim tstServer As Net.Sockets.TcpListener
 
    ' This delegate enables asynchronous calls for setting
    ' the text property on a TextBox control.
    Delegate Sub SetTextCallback(ByVal [text] As String)
 
    Private Sub Form1_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Leave
        MyDataStream.Close()
        tstServer.Stop()
        thrListen.Abort()
    End Sub
 
    Private Sub BtnListen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnListen.Click
        tstServer = New Net.Sockets.TcpListener(Net.IPAddress.Any, Int(Val(TxtPort.Text)))
        thrListen.IsBackground = True
        thrListen.Start()
    End Sub
    Private Sub DoListen()
        Dim TempString As String
        TempString = ""
        Do
            Try
                'start the listening
                tstServer.Start()
                'Accept the pending client connection and return             
                'a TcpClient initialized for communication. 
                Client = tstServer.AcceptTcpClient
                ' Get the stream
                MyDataStream = Client.GetStream
                ' Read the stream into a byte array
                Dim bytes(Client.ReceiveBufferSize) As Byte
                MyDataStream.Read(bytes, 0, CInt(Client.ReceiveBufferSize))
                ' Return the data received from the client to the txtchat textbox.
                TempString = Encoding.ASCII.GetString(bytes)
                Me.SetText(TempString)
            Catch
                MsgBox(Err.Description)
            End Try
        Loop
    End Sub
 
 
    ' This method demonstrates a pattern for making thread-safe
    ' calls on a Windows Forms control. 
    '
    ' If the calling thread is different from the thread that
    ' created the TextBox control, this method creates a
    ' SetTextCallback and calls itself asynchronously using the
    ' Invoke method.
    '
    ' If the calling thread is the same as the thread that created
    ' the TextBox control, the Text property is set directly. 
 
    Private Sub SetText(ByVal [text] As String)
 
        ' InvokeRequired required compares the thread ID of the
        ' calling thread to the thread ID of the creating thread.
        ' If these threads are different, it returns true.
        If Me.TxtChat.InvokeRequired Then
            Dim d As New SetTextCallback(AddressOf SetText)
            Me.Invoke(d, New Object() {[text]})
        Else
            'Me.TxtChat.Text = Me.TxtChat.Text & [text]
            CheckMessege([text])
        End If
    End Sub
 
    Private Sub BtnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnSend.Click
        If Client.Connected = True Then
            If MyDataStream.CanWrite Then
                Try
                    ' Do a simple write.
                    Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(TxtMessege.Text)
                    MyDataStream.Write(sendBytes, 0, sendBytes.Length)
                    'add the text to the local text box window
                    TxtChat.Text = TxtChat.Text & TxtMessege.Text
                    'clear the user messege that was typed
                    TxtMessege.Text = ""
                Catch
                    MsgBox(Err.Description)
                End Try
            End If
        Else
            TxtChat.Text = TxtChat.Text & "No Client is connected." & vbNewLine
        End If
    End Sub
    Private Sub CheckMessege(ByVal [text] As String)
        'MsgBox([text])
        Dim TempMessege() As String
        TempMessege = Split([text], "|-|")
        Select Case TempMessege(0)
            Case "Messege:"
                TxtChat.Text = TxtChat.Text & TempMessege(2) & ": " & TempMessege(1) & vbNewLine
                SendNotice("RCVD") 'Call to Send Notice sub
            Case "NewUser:"
                TxtUserList.Text = TxtUserList.Text & TempMessege(2) & vbNewLine
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " Connected"
                SendNotice("RCVD") 'Call to Send Notice sub
            Case "Disconnect:"
                TxtUserList.Text.Replace(TempMessege(2) & vbNewLine, "")
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " Disconnected"
                SendNotice("RCVD") 'Call to Send Notice sub
            Case "Connect:"
                MsgBox("Connected")
            Case Else
                MsgBox("***!!!" & vbNewLine & "---" & [text] & "---")
                SendNotice("ERR") 'Call to Send Notice sub
        End Select
    End Sub
    'SendNotice(STRING)
    '
    'Value being sent is String
    '
    'Takes a string, converts it to a byte array
    'Then sends the data on the DataStream.
    Private Sub SendNotice(ByVal MyNotice As String)
        Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(MyNotice)
        MyDataStream.Write(sendBytes, 0, sendBytes.Length)
    End Sub
End Class

I just found this out about tcpclient.nodelay, but that didn't solve the problem of the missing packets/data.

http://msdn2.microsoft.com/en-us/lib...ay(vs.80).aspx

I just don't understand why data is not being sent.

Thanks, I'll give that a try on my side.
Since I'm in office now, you have to wait for results!

One qustion for you, the messages that don't get to your server, are they shown if the client loggs off?

It doesn't work with NoDelay=True for me either!
I'm just trying to Send a message from Client, Disconnect (now the Server gets the message) and reconnect. Doing that via the controlbuttons (by hand) works fine, however if I change the Send routine and put connection_Close and Connect in it it doesn't do it. Maybe I have to wait for sencomplete (if I get something like that). This would be on the client side!

[Edit] Using the Sendcomplete for disconnecting and connecting does the job, now I have to make that into a VB2005 Clinet instead of a VB6 one!

rack, I see one difference in the TCPListener from your code compared to mine, you start the listener in your DoListen Sub, I do that in the Btton_Click routine where the thrListen is also started.Although the outcome is the same (messages from the client don'T come thru) your code is forcing my cpu to be at 100% all the time, while is only doing that until the client connected!

Hi, rack, I'm still doing further research.
It looks to me as if the DoListen Sub is stopped when the Client gets accepted "Client = tstServer.AcceptTcpClient". The next time this routine is jumped to is when the client closes the connection? The problem is I don't understand why!

Here is that UDP example I posted about before...

Its UDP not TCP even thaugh the zip says TCP, but who cares, it sends and receives bytes and encodes them to ascii...
This example has 4 sub routines, form load, background worker do work, report progress, and a button click, all are quite simple to understand, I have only tested it sending to 127.0.0.1 and have not encountered 1 problem...

Yeah I notice that for whatever reason, the server will receive the first messege, send a responce, and then, for whatever reason in my code, never again tries to get the data from the stream. I'm so close to the answer I can taste it, if someone knows what stupid coding mistake i'm making, please tell me.

I'm getting responces back and forth now, but the split I call on the messege leaves the length of the last item at 8156, which is odd.

How can I correctly split/receive the data into an array, so that the last item doesn't get the remaining blankness of the buffer.

Alright!!!!!!!!!!!!!!

Here is my working TCP Server(tcplistener), and the test User(tcpclient)

The server only supports one user so far. I'm going to create a class/structure that will hold the information for 4 users to connect.

The objects on the form are the same from the earlyer posts.
If anyone can inform me of a better way for TCP connection (not UDP) let me know, this is all i've found, reading, testing, trying random changes to code, etc.

Anyways, hers the server.

vb Code:

Imports System.Net.Sockets
Imports System.Text
Public Class Form1
    Dim thrListen As New Threading.Thread(AddressOf DoListen)
    Dim MyDataStream As System.Net.Sockets.NetworkStream
    Dim Client As Net.Sockets.TcpClient
    Dim tstServer As Net.Sockets.TcpListener
    Dim ClientStatus As Integer
    ' This delegate enables asynchronous calls for setting
    ' the text property on a TextBox control.
    Delegate Sub SetTextCallback(ByVal [text] As String)
 
    Private Sub Form1_Leave(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Leave
        MyDataStream.Close()
        tstServer.Stop()
        thrListen.Abort()
    End Sub
 
    Private Sub BtnListen_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnListen.Click
        tstServer = New Net.Sockets.TcpListener(Net.IPAddress.Any, Int(Val(TxtPort.Text)))
        'start the listening
        tstServer.Start()
        'Make sure the Thread closes if the application does
        thrListen.IsBackground = True
        'start the Listen Thread (DoListen Sub)
        thrListen.Start()
    End Sub
    Private Sub DoListen()
        Dim TempString As String
        TempString = ""
        Do
 
            Try
                If ClientStatus = 0 Then
                    'Accept the pending client connection and return             
                    'a TcpClient initialized for communication. 
                    Client = tstServer.AcceptTcpClient
                    ClientStatus = 1
                End If
                If ClientStatus = 1 Then
                    ' Get the stream
                    MyDataStream = Client.GetStream
                    ClientStatus = 2
                End If
                If ClientStatus = 2 Then
                    ' Read the stream into a byte array
                    Dim bytes(Client.ReceiveBufferSize) As Byte
                    MyDataStream.Read(bytes, 0, CInt(Client.ReceiveBufferSize))
                    ' Return the data received from the client to the txtchat textbox.
                    TempString = Encoding.ASCII.GetString(bytes)
                    Me.SetText(TempString)
                End If
            Catch ex As Exception
                MsgBox(ex.Message)
            End Try
        Loop
    End Sub
 
 
 
    ' This method demonstrates a pattern for making thread-safe
    ' calls on a Windows Forms control. 
    '
    ' If the calling thread is different from the thread that
    ' created the TextBox control, this method creates a
    ' SetTextCallback and calls itself asynchronously using the
    ' Invoke method.
    '
    ' If the calling thread is the same as the thread that created
    ' the TextBox control, the Text property is set directly. 
 
    Private Sub SetText(ByVal [text] As String)
 
        ' InvokeRequired required compares the thread ID of the
        ' calling thread to the thread ID of the creating thread.
        ' If these threads are different, it returns true.
        If Me.TxtChat.InvokeRequired Then
            Dim d As New SetTextCallback(AddressOf SetText)
            Me.Invoke(d, New Object() {[text]})
        Else
            'Me.TxtChat.Text = Me.TxtChat.Text & [text]
            CheckMessege([text])
        End If
    End Sub
 
    Private Sub BtnSend_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles BtnSend.Click
        If Client.Connected = True Then
            If MyDataStream.CanWrite Then
                Try
                    ' Do a simple write.
                    Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(TxtMessege.Text)
                    MyDataStream.Write(sendBytes, 0, sendBytes.Length)
                    'add the text to the local text box window
                    TxtChat.Text = TxtChat.Text & TxtMessege.Text
                    'clear the user messege that was typed
                    TxtMessege.Text = ""
                Catch
                    MsgBox(Err.Description)
                End Try
            End If
        Else
            TxtChat.Text = TxtChat.Text & "No Client is connected." & vbNewLine
        End If
    End Sub
    Private Sub CheckMessege(ByVal [text] As String)
        Dim TempMessege() As String
        TempMessege = Split([text], "|-|")
        If UBound(TempMessege) < 2 Then
            'this means the information provided with the messege did not contain everything needed.
            SendNotice("<-REPEAT->") 'Call to Send Notice sub
            Exit Sub
        Else
            'the only way I could figure out how to find the end of the messege.
            'this simply removes anything after the special character sequest |=|
            TempMessege(2) = Mid(TempMessege(2), 1, (InStr(TempMessege(2), "|=|") - 1))
        End If
        Select Case TempMessege(0)
            Case "Messege:"
                'this displays the username: Messege as such.
                TxtChat.Text = TxtChat.Text & TempMessege(2) & ": " & TempMessege(1) & vbNewLine
                SendNotice("<-RCVD->") 'Call to Send Notice sub
            Case "NewUser:"
                'this adds the username to the list of connected users.
                TxtUserList.Text = TxtUserList.Text & TempMessege(2) & vbNewLine
                'this displays User: Username -Connected-
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " -Connected-" & vbNewLine
                SendNotice("<-RCVD->") 'Call to Send Notice sub
            Case "Disconnect:"
                'this next line removes the user and the chr(13) or VBNEWLINE
                TxtUserList.Text = Replace(TxtUserList.Text, TempMessege(2) & vbNewLine, "")
                'This Notifies anyone in chat of the user who disconnect.
                TxtChat.Text = TxtChat.Text & "User: " & TempMessege(2) & " D-isconnected-" & vbNewLine
                SendNotice("<-RCVD->") 'Call to Send Notice sub
                'close the networkstream with this user.
                MyDataStream.Close()
                'close the connection with this user.
                Client.Close()
                'reset the variable that allows my program to work.
                ClientStatus = 0
            Case "Connect:"
                MsgBox("Connected")
            Case Else
                MsgBox("***!!!" & vbNewLine & "---" & [text] & "---")
                SendNotice("<-ERR->") 'Call to Send Notice sub
        End Select
    End Sub
    'SendNotice(STRING)
    '
    'Value being sent is String
    '
    'Takes a string, converts it to a byte array
    'Then sends the data on the DataStream.
    Private Sub SendNotice(ByVal MyNotice As String)
        Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes(MyNotice)
        MyDataStream.Write(sendBytes, 0, sendBytes.Length)
    End Sub
End Class

Here is the client.

vb Code:

Imports System.Net.Sockets
Imports System.Text
Class TCPCli
    Shared Sub Main()
 
        Dim tcpClient As New System.Net.Sockets.TcpClient()
        tcpClient.Connect("192.168.1.100", 45000)
        tcpClient.NoDelay = True
        Dim networkStream As NetworkStream = tcpClient.GetStream()
        If networkStream.CanWrite And networkStream.CanRead Then
            ' Do a simple write.
            Dim sendBytes As [Byte]() = Encoding.ASCII.GetBytes("NewUser:|-|ConnectMessege|-|Jeremy|=|")
            networkStream.Write(sendBytes, 0, sendBytes.Length)
 
            Dim bytes2(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes2, 0, CInt(tcpClient.ReceiveBufferSize))
            Dim returndata2 As String = Encoding.ASCII.GetString(bytes2)
            Console.WriteLine(("Data was:" + returndata2))
 
            Dim sendBytes2 As [Byte]() = Encoding.ASCII.GetBytes("Messege:|-|Whats going on?|-|BoB|=|")
            networkStream.Write(sendBytes2, 0, sendBytes2.Length)
            If tcpClient.NoDelay = False Then Console.WriteLine("Delay")
  
            ' Read the NetworkStream into a byte buffer.
            Dim bytes(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes, 0, CInt(tcpClient.ReceiveBufferSize))
            ' Output the data received from the host to the console.
            Dim returndata As String = Encoding.ASCII.GetString(bytes)
            Console.WriteLine(("Host returned: " + returndata))
 
            Dim sendBytes3 As [Byte]() = Encoding.ASCII.GetBytes("Disconnect:|-||-|Jeremy|=|")
            networkStream.Write(sendBytes3, 0, sendBytes3.Length)
 
            Dim bytes3(tcpClient.ReceiveBufferSize) As Byte
            networkStream.Read(bytes3, 0, CInt(tcpClient.ReceiveBufferSize))
 
            Dim returndata3 As String = Encoding.ASCII.GetString(bytes3)
            Console.WriteLine(("Recvied what: " + returndata3))
        Else
            If Not networkStream.CanRead Then
                Console.WriteLine("cannot not write data to this stream")
                tcpClient.Close()
            Else
                If Not networkStream.CanWrite Then
                    Console.WriteLine("cannot read data from this stream")
                    tcpClient.Close()
                End If
            End If
        End If
        ' pause so user can view the console output
        Console.ReadLine()
    End Sub
End Class

Quote:

---

Originally Posted by rack

I'm getting responces back and forth now, but the split I call on the messege leaves the length of the last item at 8156, which is odd.

---

Which "split", I don't see something like that in your code, or do I have a language problem?

The split command on line 107 of the most recent server code snipet showing in the post just before your post.

[EDIT]

Good night, i'm going to bed now, the happiness in me is overwhelmed by the lack of sleep.

[EDIT 2]

Also, I know that what is happening is, while reading, I am reading the length of the read BUFFER, not the length of the read DATA. I don't know how to gather the length of the read DATA. I tried changing the tcpclient.SendBuffer on the User (client) but I believe because the Receive buffer is still 8092 or something it ends up getting a 8093 lenth byte array/string.

So if you find out how to check the Receive read DATA let me know.

Other then the way I am currently using (flagging the end of the messege).
Other then sending the length of the messege with the messege, before the messege, (and useing the mid fucntion still).

Have a good one, i'm going to test this code on my side later this day (European Time!)

Sendind and receiving works like a charm, however I have a problem if the client disconnects. Your code will receive empty messages in a endless loop.
I put in this change:

Code:

---

                If ClientStatus >= 2 Then
                    If ClientStatus > 2 And TempString = "" Then
                        Exit Do
                    End If
                    ' Read the stream into a byte array
                    Dim bytes(Client.ReceiveBufferSize) As Byte
                    MyDataStream.Read(bytes, 0, CInt(Client.ReceiveBufferSize))
                    ' Return the data received from the client to the txtchat textbox.
                    TempString = Encoding.ASCII.GetString(bytes)
                    Me.SetText(TempString)
                    ClientStatus = 3
                End If

---

The Tempstring is "" when the first empty message arrives after disconnecting, however the Check Tempstring="" returns FALSE! I don't get it????

Ah, I see. I added a check for if the connection was still there. And an err.number check.

I am going to start working on the Windows Client app now.

Also, you may want to change my spelling errors for the word "Message" in all of the code.

Here are some of the changes, starting from the begining.

This was just to add the information about what the different values of Clientstatus mean.

vb Code:

Dim ClientStatus As Integer
    'Clientstatus
    '0 = Disconnected
    '1 = Connected to User
    '2 = DataStream Connected (able to receive and send messeges)

This code goes just after the if Clientstatus=2 then line.

vb Code:

If Client.Connected = False Then
                        If ClientStatus > 1 Then
                            MyDataStream.Close()
                        End If
                        If ClientStatus > 0 Then
                            Client.Close()
                        End If
                        ClientStatus = 0
                        Exit Try
                    End If

This is the entire section from the Catch, to the End try in the DoListen Sub.

vb Code:

Catch ex As Exception
                Select Case Err.Number
                    Case 57 'Connection Forcibly closed by Remote Host.
                        ''Actual Error Messege Below
                        ''Unable to read data from the transport connection: 
                        ''An existing connection was forcibly closed by the remote host.
 
                        'Assume the user disconnected without sending a Disconnect messege.
 
                        If ClientStatus > 1 Then
                            MyDataStream.Close()
                        End If
                        If ClientStatus > 0 Then
                            Client.Close()
                        End If
                        ClientStatus = 0
                    Case Else
                        MsgBox(ex.Message & vbNewLine & "Error Number:" & Err.Number & vbNewLine & "Source:" & ex.Source & vbNewLine & "StackTrace:" & ex.StackTrace)
                End Select
            End Try

Added this to the Select Case TempMessege(0) in the CheckMessege Sub.

vb Code:

Case ">-Internal-<"
                Select Case TempMessege(1)
                    Case "USERDISCONNECT"
                        'Send messege to other users.
                        'Let them know of the disconnect.
                        'Update list.
                        'TempMesssege(2) will contain the username.
                    Case Else
 
                End Select
            Case "<-REPEAT->"
                'put code hear to repeat last message sent.
            Case "<-RCVD->"
                'Do nothing, the data that was sent, was received.
            Case "<-ERR->"
                MsgBox("There was an error attempting to send the last peice of data.")

OK, will give it try tonight (I my family will give me the time, we're just prior leaving for summer-vacation).

I see your checking for Client.connected=False, I checked on that, but it showed true??? all the time, although the connection was closed (without sending anything)from the other side. That'S the reason I was doing this try with the ClientStatus=3 and TempString="". I'm still wondering why a TempString="" would make a FALSE although TempString=""??

Here are the two projects.
Both have similar functions in them. Both are windows applications with textboxes, and buttons.

For some reason, the threading on the Client makes the CPU usage jump to 50%, I don't know why, because I don't know much at all about threading. If anyone sees my error, let me know please.

Tcp - NS - Listener is the server.
TCP - CLient 2 is the User.

Open the Listener, click Listen.
Open the CLient, click Connect.

Make sure to edit the IP address to whatever you want to use 127.0.0.1 or whatever.

Listener (Server)
TCP - NS - Listener.zip
Client (User)
TCP - Client 2.zip

Hi rack,
tried to get the attachments of your post, got a message about invalid attachment instead, please recheck.

Tested it, the problem with the closed connection remains, my Client.Connected is still true, that way your If Clause doesn't do it. The check with an empty Tempstring would do it, however out off an unknown reason " TempString = "" " returns FALSE altough Tempstring="" ????? I tried it with also with VbNullChar and Nothing. I'm out off any clue!

Do you have the example "VB.NET - Advanced .NET Framework (Networking) - Use Sockets" it has an example of client server?

The "VB.NET - Advanced .NET Framework (Networking) - Use Sockets"
If I can get my GPRS line to upload 182K ??

@thered:
Thanks, I'll look into that example as well.

@rack:
We are leaving for two weeks vacation in Denmark, so you won't get any answer from me for next couple of days. Thanks a lot so far.

Apparantly i'm an idiot and had too many windows open, uploaded them to one, but posted with the other window I think.

Anyways, marking this resolved, as I have answered my questions myself. I have other questions, but that requires another thread.


{EDIT}
07/20/2007

I'd check with the admins, maybe the ZIP was to big, did hold something that wasn't supposed to be posted ....

I updated a few things in the code.

Found an error that was causing the client and server to both just keep sending <-REPEAT-> commands back and forth to each other.

Added threader.thread.sleep(100) so that the listener threads won't cause 30-50% processor usage.

Edited a few other things so that the send button displays the your name, in your chat window, when you type a message.