TCP Listener

dotdotnet

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Joined
Aug 19, 2003
Messages
9
I have this following code written and running as a windows service. Each time some data is received, the data will be written to the log file. However, after i send more than 1 set of data to that listening port, it simply would not record in the logfile more than 1 record, anyone can show me what is wrong with my codes? and 1 more thing, is it possible or advisable to use a window service such as this to store the data it received to a database via ODBC or do i need to create another project to talk to this windows service? if so, how should i go about doing it? thanks.

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

Private Listener As TcpListener
Private StopListener As Boolean
Private AlreadyConnected As Boolean = False
Private LogFile = "c:\temp\test.log"
Private StateObject As StateObjectClass
Private TEST_ID As String
Private Default_TEST_ID = "TEST01"
Private CIL_Len As Integer
Private TCP_Port As Integer
Private myLog As Common.myEventLog

Protected Overrides Sub OnStart(ByVal args() As String)

myLog = New Common.myEventLog()
myLog.mySource = "TCPIP"
myLog.WriteToLog("TCPIP Started.")

WriteToLogFile("Service Started.")

If args.Length = 0 Then
TEST_ID = Default_TEST_ID
Else
If Len(args(0)) = 4 Then
TEST_ID = args(0)
Else
TEST_ID = Default_TEST_ID
End If
End If

WriteToLogFile("TEST_ID = " + TEST_ID)

CIL_Len = 116
TCP_Port = 6006

Listener = New TcpListener(TCP_Port)

Listener.Start()

StateObject = New StateObjectClass()

Dim timerDelegate As New TimerCallback(AddressOf TimerTick)
Dim timer As New Timer(timerDelegate, StateObject, 1000, 1000)

StateObject.TimerReference = timer

End Sub

Protected Overrides Sub OnStop()
StopListener = True
Listener.Stop()
StateObject.TimerReference.Dispose()
myLog.WriteToLog("TCPIP Stopped.")
WriteToLogFile("Service Stopped.")
End Sub

Protected Sub ProcessRequest()

Dim CurSocket As Socket
Dim Buffer(CIL_Len) As Byte
Dim Bytes As Integer
Dim IncomingString As String
Dim LeftOverString As String

WriteToLogFile("Connection established.")

CurSocket = Listener.AcceptSocket

While Not StopListener

If CurSocket.Available > 0 Then

Bytes = CurSocket.Receive(Buffer, Buffer.Length, 0)
WriteToLogFile("Bytes = " + Bytes.ToString)

IncomingString = System.Text.Encoding.Default.GetString(Buffer)

If Bytes = CIL_Len And IncomingString.Substring(2, 1) = " " Then
ProcessString(Left(IncomingString, CIL_Len - 5))
Else
WriteToLogFile(IncomingString)
End If
Else
System.Threading.Thread.CurrentThread.Sleep(100)
End If

If Not CurSocket.Connected Then
StopListener = True
End If
End While

CurSocket.Close()
AlreadyConnected = False

WriteToLogFile("Connection dropped.")

End Sub

Private Sub ProcessString(ByVal Str As String)

WriteToLogFile(Str)
Dim Logger As New localhost.CallLogging()
Logger.LogData(TEST_ID, Str)

End Sub

Private Sub WriteToLogFile(ByVal strLog As String)
FileOpen(1, LogFile, OpenMode.Append, OpenAccess.Write, OpenShare.Shared)
PrintLine(1, "(" + Now + ")" + vbCrLf + strLog)
FileClose(1)
End Sub

Private Sub TimerTick(ByVal StateObj As Object)
If Not Listener.Pending() Then
Exit Sub
End If

If Not AlreadyConnected Then
AlreadyConnected = True
ProcessRequest()
End If

End Sub
End Class

Class StateObjectClass
Public TimerReference As System.Threading.Timer
Public TimerCanceled As Boolean
End Class
 
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