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Winsock Control - Control array DataArrival event

Posted on 1997-09-17
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Last Modified: 2013-11-13
Hi,
  I'm trying to create a simple server application that will accept incoming data from a client application.  I'm trying to do what the examples say to do on pp 174-176 of the VB Components Tool Guide (using the Winsock Control).  I need to be able to accept more than 1 connection request at a time, so I'm trying to create a control array as follows...

Private intMax As Long

Private Sub Form_Load()
    intMax = 0
    tcpServer(0).LocalPort = 2345
    tcpServer(0).Listen
End Sub

Private Sub tcpServer_ConnectionRequest _
(Index As Integer, ByVal requestID As Long)
    If Index = 0 Then
        intMax = intMax + 1
        Load tcpServer(intMax)
        tcpServer(intMax).LocalPort = 0
        tcpServer(intMax).Accept requestID
        Load txtData(intMax)
    End If
End Sub

...so far so good.  I've followed instructions by setting the index property of tcpServer to 0 which supposedly creates the array.  I also did likewise with txtData.  I'm not sure if txtData is supposed to display the incoming data from the client, but I'm assuming it is.  The instructions don't say.
Now I complete the scenario by including the event procedure for the arrival of the data...

Private Sub tcpServer(intMax)_DataArrival(ByVal bytesTotal As Long)
    ' Declare a variable for the incoming data.
    ' Invoke the GetData method and set the Text
    ' property of a TextBox named txtOutput to
    ' the data.
    Dim strData As String
    tcpServer(intMax).GetData strData
    txtData(intMax).Text = strData
End Sub

...and I get a compiler error saying that the underscore in the procedure declaration is an invalid character.  ((inMax)_DataArrival).  If this is invalid then why is it not also invalid in scalar context...

Private Sub tcpServer_DataArrival(ByVal bytesTotal As Long)   ???

...If I leave out the (intMax), I get an error that states that the Procedure declaration does not match the description of event or procedure having the same name.  How should I handle this?
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Question by:zingbust
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4 Comments
 
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Accepted Solution

by:
volking earned 100 total points
ID: 1435288
You've got a syntax error ...
Try ...

Private Sub tcpServer_DataArrival (Index as Integer, ByVal bytesTotal As Long)

Which incident of tcpServer is passed as a parameter Index.
In your example, "Index as integer" is replacing "intMax".

===========> Frederick Volking
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Expert Comment

by:volking
ID: 1435289
I'd rewrite your sub like this ...

Private Sub tcpServer_DataArrival(Index as integer, ByVal bytesTotal As Long)
      ' Declare a variable for the incoming data.
      ' Invoke the GetData method and set the Text
      ' property of a TextBox named txtOutput to
      ' the data.
      Dim strData As String
      tcpServer(index).GetData strData
      txtData(index).Text = strData
End Sub
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LVL 5

Expert Comment

by:volking
ID: 1435290
Or even like this ...

Private Sub tcpServer_DataArrival(Index as integer, ByVal bytesTotal As Long)
      tcpServer(index).GetData txtData(index).Text
End Sub
0
 
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Expert Comment

by:volking
ID: 1435291
I might also suggest caution in handling the results in txtData(index).Text the actual string you get returned may be suffixed with garbage which happens to be left in the recieve buffer so I'd improve the above like this to safeguard:

Private Sub tcpServer_DataArrival(Index as integer, ByVal bytesTotal As Long)
      tcpServer(index).GetData txtData(index).Text
      txtData(index).Text = left$(txtData(index).Text, bytesTotal)
End Sub

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