"WildBill" <wsbr***@gmail.com> wrote in message
news:1165212625.121316.89420@73g2000cwn.googlegroups.com...
>I am using a tcpclient and a network stream to communicate with the TCP
> port on a printer for testing the printer firmware.
> The code I have works perfectly the first time I run it. The printer
> reacts correctly.
> If I run it again there is a long delay before the the printer reacts.
>
> When we used VB6 sockets to do this we had no problems.
> Below is the code I am using in Visual Studio 2005
> Any help would be appreciated.
>
> Public Function SendReceive(ByVal strMechCommand As String, _
>                                             ByRef strReturnedData As
> String) As Boolean
>            '--- Create a TcpClient ---
>            Try
>                printer = New TcpClient(mIPAddress, Port)
>                printer.NoDelay = True
>                mConnected = True
>                '--- Get a client stream for reading and writing ---
>                stream = printer.GetStream()
>
>            Catch er As Exception
>                mErrorMessage = er.Message
>                Try
>                    stream.Dispose()
>                    printer.Close()
>                Catch err As Exception
>                    mErrorMessage = mErrorMessage & vbCrLf & "No
> Connections to close."
>                End Try
>            End Try
>
>            '--- If the printer is connected
>            If printer.Connected And stream.CanWrite And stream.CanRead
> Then
>                Try
>                    Dim mechCommand As [Byte]() =
> System.Text.Encoding.ASCII.GetBytes(strMechEnter & strMechCommand &
> strMechExit)
>                    stream.Write(mechCommand, 0, mechCommand.Length)
>                    Thread.Sleep(300)
>                    '--- If return data is expected then go get it ---
>                    If strReturnedData <> "SendOnly" Then
>                        '--- Create variable to create a Buffer to
> store the response bytes ---
>                        Dim received_data = New [Byte](1024) {}
>                        '--- Create a string to store the response
> ASCII representation ---
>                        Dim received_string As [String] =
> [String].Empty
>                        '--- Create a variable to store the number of
> bytes received ---
>                        Dim bytes As Int32
>                        '--- Create a counter variable ---
>                        Dim count As Integer = 0
>                        '--- Loop that waits for upto 4 seconds for
> data to be returned --
>                        While stream.DataAvailable = False
>                            Thread.Sleep(100)
>                            count += 1
>                            If count > 40 Then
>                                mErrorMessage = "Timeout while waiting
> for data."
>                                Disconnect()
>                                Exit Function
>                            End If
>                        End While
>                        '--- Loop that reads data 1024 bytes at a time
> till all data received ---
>                        While stream.DataAvailable
>                            bytes = stream.Read(received_data, 0,
> received_data.Length)
>                            received_string +=
> System.Text.Encoding.ASCII.GetString(received_data, 0, bytes)
>                            Thread.Sleep(500)
>                        End While
>                        Disconnect()
>                        strReturnedData = received_string
>                    Else
>                        Disconnect()
>                        strReturnedData = ""
>                    End If
>                    Return True
>                Catch err As Exception
>                    mErrorMessage = err.Message
>                    Disconnect()
>                    Return False
>                End Try
>            Else
>                mErrorMessage = "SendReceive method: No Connection to
> printer found"
>                mConnected = False
>                Disconnect()
>                Return False
>            End If
>        End Function
>