[VB.NET] Problem on socket

jcgo16 · Jun 11, 2013

i found on google in some website

when i try to send this on the client

Code:

   Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)

the client will show

Code:

woot
wootwootwootwootwootwoot

but i like to see

Code:

woot
woot
woot
woot
woot
woot

whats the problem in the code?

any ideas?

SERVER CODE

Code:

Imports System.Net.Sockets
Imports System.Net

Public Class Form1
    Dim serverSocket As Socket
    Dim clientSocket As Socket
    Dim byteData(1023) As Byte
    Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
        serverSocket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        Dim IpEndPoint As Net.IPEndPoint = New Net.IPEndPoint(IPAddress.Any, 8800)
        serverSocket.Bind(IpEndPoint)
        serverSocket.Listen(50)
        serverSocket.BeginAccept(New AsyncCallback(AddressOf OnAccept), Nothing)
    End Sub
    Public Sub Send(ByVal msg As String, ByVal client As Socket)
        Dim sendBytes As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(msg)
        client.BeginSend(sendBytes, 0, sendBytes.Length, SocketFlags.None, New System.AsyncCallback(AddressOf OnSend), client)
        Array.Clear(byteData, byteData.GetLowerBound(0), byteData.Length)
    End Sub
    Private Sub OnSend(ByVal ar As IAsyncResult)
        Dim Client As Socket = ar.AsyncState
        Client.EndSend(ar)
    End Sub
    Delegate Sub _OnRecieve(ByVal ar As IAsyncResult)
    Private Sub OnRecieve(ByVal ar As IAsyncResult)
        If InvokeRequired Then
            Invoke(New _OnRecieve(AddressOf OnRecieve), ar)
            Exit Sub
        End If
        Dim client As Socket = ar.AsyncState
        Try
            client.EndReceive(ar)
            Dim bytesRec As Byte() = byteData
            Dim message As String = System.Text.ASCIIEncoding.ASCII.GetString(bytesRec)
            clientSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None, New AsyncCallback(AddressOf OnRecieve), clientSocket)

        Catch ex As Exception
        End Try
    End Sub
    Private Sub OnAccept(ByVal ar As IAsyncResult)
        clientSocket = serverSocket.EndAccept(ar)
        serverSocket.BeginAccept(New AsyncCallback(AddressOf OnAccept), Nothing)
        clientSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None, New AsyncCallback(AddressOf OnRecieve), clientSocket)
        AddClient(clientSocket)
    End Sub
    Delegate Sub _AddClient(ByVal client As Socket)
    Private Sub AddClient(ByVal client As Socket)
        If InvokeRequired Then
            Invoke(New _AddClient(AddressOf AddClient), client)
            Exit Sub
        End If
    End Sub
    Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
        Send("woot", clientSocket)
    End Sub
End Class

CLIENT CODE

Code:

Imports System.Net.Sockets
Imports System.Net



Public Class Form1
 Dim clientSocket As Socket
    Dim byteData(1023) As Byte
 Private Sub OnConnect(ByVal ar As IAsyncResult)
        Try
            clientSocket.EndConnect(ar)
            restarttimer()
            Send("username:" & Environment.UserName, clientSocket)
            clientSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None, New AsyncCallback(AddressOf OnRecieve), clientSocket)
        Catch ex As Exception
            reconnectdata()
        End Try
    End Sub
    Public Sub Send(ByVal msg As String, ByVal client As Socket)
        Dim sendBytes As Byte() = System.Text.ASCIIEncoding.ASCII.GetBytes(msg)
        client.BeginSend(sendBytes, 0, sendBytes.Length, SocketFlags.None, New AsyncCallback(AddressOf OnSend), client)
    End Sub
    Private Sub OnSend(ByVal ar As IAsyncResult)
        Dim client As Socket = ar.AsyncState
        client.EndSend(ar)
    End Sub
    Delegate Sub _OnRecieve(ByVal ar As IAsyncResult)
    Private Sub OnRecieve(ByVal ar As IAsyncResult)
        If InvokeRequired Then
            Invoke(New _OnRecieve(AddressOf OnRecieve), ar)
            Exit Sub
        Else
            Dim client As Socket = ar.AsyncState
            Try
                client.EndReceive(ar)
                Dim message As String = System.Text.ASCIIEncoding.ASCII.GetString(byteData)
                Read(message)
                clientSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None, New AsyncCallback(AddressOf OnRecieve), client)
            Catch ex As Exception
                clientSocket.Disconnect(False)
                reconnectdata()
            End Try
        End If
    End Sub

  Private Sub Read(ByVal msg As String)
                ListBox1.Items.Add(msg)
                ListBox1.SelectedIndex = ListBox1.Items.Count - 1
               Array.Clear(byteData, byteData.GetLowerBound(0), byteData.Length)

    End Sub
  Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
 System.Threading.Thread.Sleep(2000)
        clientSocket = New Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp)
        Dim ipAddress As IPAddress = ipAddress.Parse(ini.ReadString("ip"))
        Dim ipEndPoint As IPEndPoint = New IPEndPoint(ipAddress, ini.ReadString("port"))
        clientSocket.BeginConnect(ipEndPoint, New AsyncCallback(AddressOf OnConnect), Nothing)
  End Sub
  
  End Class

Josh Cell · Jun 11, 2013

Can you try with it?

Code:

        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)

jcgo16 · Jun 11, 2013

still the same

when i try only these
Code:
 Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
the output is
Code:
woot
woot
when i add more
the output will be this
Code:
woot
wootwoot

Josh Cell · Jun 11, 2013

Have you tried to send a couple of data in one packet instead of doing it separately?

Something like that:
Code:
Send("woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine &
"woot" & vbNewLine, clientSocket)
I have seen no issue around your code.

jcgo16 · Jun 11, 2013

becuase im trying to send words or commands in new line but still the same

Send("computerresetcommand",clientsocket)

Send("shuttingdown",clientsocket)

Send("messageshowme",clientsocket)

jcgo16 · Jun 11, 2013

so what i did is to count what i send from server to client, the server looks good and ok on the sending, but the client only receive 2, i don't know whats the problem but still working and giving clues

Josh Cell · Jun 11, 2013

Hmm, ok.

Try to replace this code by this another one:

OLD:
Code:
Array.Clear(byteData, byteData.GetLowerBound(0), byteData.Length)
NEW:
Code:
byteData = New Byte(1023) { }

jcgo16 · Jun 11, 2013

yup still the same, damn i think theres something wrong with the client i think, i dont know what line, when i send 3 or more the second and up will stacked each other
woot << 1st send
wootwootwoot <<< 2nd 3rd and 4th send, i think theres something wrong with this line

Code:

    Delegate Sub _OnRecieve(ByVal ar As IAsyncResult)
    Private Sub OnRecieve(ByVal ar As IAsyncResult)
        If InvokeRequired Then
            Invoke(New _OnRecieve(AddressOf OnRecieve), ar)
            Exit Sub
        Else
            Try
                Dim client As Socket = ar.AsyncState
                client.EndReceive(ar)
                Dim message As String = System.Text.ASCIIEncoding.ASCII.GetString(byteData)
                Read(message)
                clientSocket.BeginReceive(byteData, 0, byteData.Length, SocketFlags.None, New AsyncCallback(AddressOf OnRecieve), client)
            Catch ex As Exception
                clientSocket.Disconnect(False)
                reconnectdata()
            End Try
        End If
    End Sub

Josh Cell · Jun 12, 2013

Try it:

Code:

  Private Sub Read(ByVal msg As String)
                ListBox1.Items.Insert(ListBox1.Items.Count, msg)
                ListBox1.SelectedIndex = ListBox1.Items.Count - 1
               Array.Clear(byteData, byteData.GetLowerBound(0), byteData.Length)

  End Sub

BobSheep · Jun 12, 2013

The problem is probably due to the Nagle Algorithm

http://support.microsoft.com/kb/214397

To avoid having small data packets congest the network, Microsoft TCP stack enables the Nagle algorithm by default, which coalesces a small data buffer from multiple send calls and delays sending it until an ACK for the previous data packet sent is received from the remote host.
Click to expand...

Michaela Joy · Jun 13, 2013

Here's something that I just found. It might help you.

http://support.microsoft.com/kb/138831

jcgo16 · Jun 13, 2013

thank you for the help, still getting the same thing, sad to say that there is a limitation

Michaela Joy · Jun 13, 2013

Have you tried setting the property "Socket.NoDelay" to true?

See Here http://msdn.microsoft.com/en-us/lib...aspx?cs-save-lang=1&cs-lang=vb#code-snippet-1

jcgo16 · Jun 13, 2013

yes, not working, kinda worried if some commands might be turn off on my server

luciferall · Feb 1, 2014

jcgo16 said: ↑
still the same

when i try only these
Code:
 Send("woot" & vbNewLine, clientSocket)
        Send("woot" & vbNewLine, clientSocket)
the output is
Code:
woot
woot
when i add more
the output will be this
Code:
woot
wootwoot
Click to expand...
modify your output box so when it recives the data does a break and adds a new line.

Private Sub Read(ByVal msg As String)
If InvokeRequired Then
Invoke(New _Read(AddressOf Read), msg)
Exit Sub
End If
RichTextBox1.AppendText(msg & vbCrLf)
RichTextBox1.ScrollToCaret()
End Sub

Private Sub SendButton_Click(sender As Object, e As EventArgs) Handles SendButton.Click
Send(InputTextBox.Text & vbNewLine, clientSocket)
End Sub

this will do the trick, it worked for me. don't forget to changes accordingly in the server and client app.

jellybelly · Feb 1, 2014

In the past whenever I was doing client/server stuff I generally always delimited commands just to avoid any situations like this (among others)... maybe there was a better way of doing things but it always worked for me.

Send("woot|", clientSocket)
Send("woot|", clientSocket)
Send("woot|", clientSocket)

And on the receiving end split by | and go from there.. whether you have one or many commands mushed together on a line it's easy peasy to process and not get any errors.
Code:
       Dim commands() As String = Split(msg, "|")
        For Each s As String In commands
            If Not String.IsNullOrEmpty(s) Then
                ' perform action
            End If
        Next
Easy but effective solution.

[VB.NET] Problem on socket

jcgo16 MDL Junior Member

Josh Cell MDL Developer

jcgo16 MDL Junior Member

Josh Cell MDL Developer

jcgo16 MDL Junior Member

jcgo16 MDL Junior Member

Josh Cell MDL Developer

jcgo16 MDL Junior Member

Josh Cell MDL Developer

BobSheep MDL Guru

Michaela Joy MDL Crazy Lady

jcgo16 MDL Junior Member

Michaela Joy MDL Crazy Lady

jcgo16 MDL Junior Member

luciferall MDL Novice

jellybelly MDL Member