Winsock Chat Server Error

Hi all...

i'm currently doing a chat server program with winsock.. it can accept mutiple connections and broadcast messages...

the server is using 2 winsocks.
1 is a active listener...
the other is a control arrays of winsock that connects the clients and server..... dynamically created when new connections come..

the problem is :
(muti-accepts are ok)...
however, when a chat client disconnects and a new client attempts to connect...
i get this
run-time 360 error
object already loaded..

i know why this happens.. its due to my array of winsock..
if a connection is accepted.. a global variable increases... and decreases when connections come n go...

example:
5 clients connect...
no. 3 decides.. to go...
another new client(x) attempts to connect... the error comes on!!

HELP...
can someone PLEASE help me with this bug???
here goes...



this is my array of winsock that accepts a client....
-------------------------------------------
------------------------------------------

Private Sub tcpServerArray_DataArrival(Index As Integer, ByVal bytesTotal As Long)
Dim strData As String
Dim strHostname As String
Dim strIpAddress As String
Dim strCommand As String

Dim i As Long

If Len(tcpServerArray(Index).RemoteHostIP) Then
strHostname = GetHostNameFromIP(tcpServerArray(Index).RemoteHostIP)
strIpAddress = tcpServerArray(Index).RemoteHostIP
Else
strIpAddress = GetIPFromHostName(tcpServerArray(Index).RemoteHost)
strHostname = tcpServerArray(Index).RemoteHost
End If

tcpServerArray(Index).GetData strData

If Left$(strData, 1) = Chr(47) Then
strCommand = ServerCommandSystem(strData)

If Len(strCommand) Then
strData = strCommand
tcpServerArray(Index).SendData strData
End If
Else
For i = 0 To tcpServerArray.UBound
tcpServerArray(i).SendData strData
Next
End If

End Sub


Private Sub tcpServerArray_SendComplete(Index As Integer)
sCommandComplete = True
End Sub


Private Sub tcpServerArray_Close(Index As Integer)

If tcpServerArray(Index).State <> sckClosed Then
Call ServerArraySocketClose(Index)
End If

End Sub


Private Sub tcpServerArray_Error(Index As Integer, ByVal Number As Integer, Description As String, ByVal Scode As Long, ByVal Source As String, ByVal HelpFile As String, ByVal HelpContext As Long, CancelDisplay As Boolean)

If tcpServerArray(Index).State <> sckClosed Then
Call ServerArraySocketClose(Index)
End If

MsgBox ("Error Occured : " & vbCrLf & Description), vbCritical, ("WinSock Error " & Number)


End Sub



here is my winsock that "listens for new connections..
--------------------------------------
------------------------------------
Private Sub tcpServer_ConnectionRequest(ByVal RequestID As Long)
Dim strHostname As String
Dim strIpAddress As String
Dim CheckClient As Boolean

'Check if the control's State is listening.
If tcpServer.State = sckListening Then

If Len(tcpServer.RemoteHostIP) Then
strHostname = GetHostNameFromIP(tcpServer.RemoteHostIP)
strIpAddress = tcpServer.RemoteHostIP
Else
strIpAddress = GetIPFromHostName(tcpServer.RemoteHost)
strHostname = tcpServer.RemoteHost
End If

'txtConnectStatus.Text = "Incoming Connection from: " & strHostname _
& " [" & strIpAddress & "]"
'txtDisplay.Text = txtDisplay.Text & Time() & " >> " _
& "Incoming Connection from: " & strHostname _
& " [" & strIpAddress & "]" _
& vbCrLf

Connections = Connections + 1
If Connections >= 1 Then Load tcpServerArray(Connections)
'The port you chose above
tcpServerArray(Connections).LocalPort = tcpServer.LocalPort
'Accept the request with the requestID parameter.
tcpServerArray(Connections).Accept RequestID

cnt = cnt + 1

'txtConnectStatus.Text = "Connection accepted from: " & strHostname _
& " [" & strIpAddress & "]"

txtDisplay.Text = txtDisplay.Text & Time() & " >> " _
& "Connection accepted from: " & strHostname _
& " [" & strIpAddress & "]" _
& vbCrLf

'lstClients.AddItem strHostname & " [" & strIpAddress & "]"

CheckClient = ArrayExists(ConnectedClients)

If CheckClient = False Then
cnt = 1
Else
cnt = cnt + 1
End If

ReDim Preserve ConnectedClients(0 To cnt) As Clients
ConnectedClients(cnt).ConnID = cnt
ConnectedClients(cnt).hostname = strHostname
ConnectedClients(cnt).IPAddress = strIpAddress

'Add Connected Client Information
lstClients.AddItem ConnectedClients(cnt).hostname & _
vbTab & _
" [" & ConnectedClients(cnt).IPAddress & "]", Connections

lstClients.ListIndex = 0

End If

End Sub


Private Sub tcpServer_Close()

If tcpServer.State <> sckClosing Then
Call ServerSocketClose
End If

End Sub


Private Sub tcpServer_Error(ByVal Number As Integer, Description As String, ByVal Scode As Long, ByVal Source As String, ByVal HelpFile As String, ByVal HelpContext As Long, CancelDisplay As Boolean)

If tcpServer.State <> sckClosed Then
Call ServerSocketClose
End If

MsgBox ("Error Occured : " & vbCrLf & Description), vbCritical, ("WinSock Error " & Number)

End Sub

Could you also include the "ServerSocketClose" sub.

I think I know the problem, but I need to be sure.

yes!!

finally some help!!



i think the prob is becoz of my winsock array no. and the listbox's index is wrong....

lets say..
there are 4 connections...
so my listbox will have 4 items now...

if no.2 leaves... it is cleared..
then the rest (3 winsock) will be "re-indexed"... to 0~3..
thats why is i close lets say connection 2... the index is now 1.. where it shouldn't be .. but becoz of the listbox' wrong inddex..

i get those errors....
am i right about this.????

but i cant seem to be able to solve this sickening bug....


thanks alot for helping.. once again....
let me know abt your results too, asap.. ok??

i have 2 functions that are "controling" the closing of sockets..... i need them to be called frequently... that why i used 2 functions to close the sockets....


Private Function ServerSocketClose()
Dim strHostname As String
Dim strIpAddress As String

If tcpServer.State <> sckClosed Then

If Len(tcpServer.RemoteHostIP) Then
strHostname = GetHostNameFromIP(tcpServer.RemoteHostIP)
strIpAddress = tcpServer.RemoteHostIP
Else
strIpAddress = GetIPFromHostName(tcpServer.RemoteHost)
strHostname = tcpServer.RemoteHost
End If

txtDisplay.Text = txtDisplay.Text & Time() & " >> " _
& "Connection from: " & strHostname _
& " [" & strIpAddress & "]" _
& " on port " & tcpServer.LocalPort _
& " Closed" _
& vbCrLf & vbCrLf
tcpServer.Close

End If

End Function


Private Function ServerArraySocketClose(ByVal Index As Integer, _
ByVal sCommand As Integer)
Dim strHostname As String
Dim strIpAddress As String
Dim i As Long

If tcpServerArray(Index).State <> sckClosed Then

If Len(tcpServerArray(Index).RemoteHostIP) Then
strHostname = GetHostNameFromIP(tcpServerArray(Index).RemoteHostIP)
strIpAddress = tcpServerArray(Index).RemoteHostIP
Else
strIpAddress = GetIPFromHostName(tcpServerArray(Index).RemoteHost)
strHostname = tcpServerArray(Index).RemoteHost
End If

Select Case sCommand
Case 0:
txtDisplay.Text = txtDisplay.Text & Time() & " >> " _
& "Connection from " _
& strHostname _
& " [" & strIpAddress & "]" _
& " dropped from server " _
& tcpServer.LocalHostName _
& " [" & tcpServer.LocalIP & "]" _
& " on port " _
& tcpServer.LocalPort _
& vbCrLf & vbCrLf
Case Else:
txtDisplay.Text = txtDisplay.Text & Time() & " >> " _
& "Connection from: " _
& strHostname _
& " [" & strIpAddress & "]" _
& " on port " _
& tcpServer.LocalPort _
& " Closed" _
& vbCrLf & vbCrLf
End Select

tcpServerArray(Index).Close
Unload tcpServerArray(Index)
'Connections = Connections - 1
ActiveConn = ActiveConn - 1
End If

End Function


***NOTE...
the serversocketclose() closes the main winsock that does the listening (only this job)

the serverarrayclose() closes the "active" (real) connections between the chat clients....

Well, theres still code missing. Either that or you "ActiveConn = ActiveConn - 1" for absolutely no reason. However, I will still give my opinion of what is going on.

I assume that the only object you are loading is the winsock control. The problem is that you are trying to load something that has already previously been loaded, as the error says.

You have said that everytime a user connects the connections counter goes up, and everytime someone leaves it goes down again. You also say that the array is reshuffled everytime someone leaves. However, as far as I know (correct me if I'm wrong), objects can't just be reshuffled. Arrays can certainly, but I'm definately not sure about objects. Take this scenario:

- Client 1 logs in, taking Index 1 and moving the connection variable to 1.
- Client 2 logs in, taking Index 2 and moving the connection variable to 2.
- Client 3 logs in, taking Index 3 and moving the connection variable to 3.

The Winsock object has been loaded 3 times, with index 1 through 3.

- Client 3 logs out, closing Index 3 and moving the connection variable to 2.
- Client 4 logs in, and attempts to take Index 2, which has already been taken by Client 2. This procures the object has already been loaded error.

To get around this you need to have a loop from 0 to infinity using a counter, to check if the winsock(counter) is currently closed or not loaded. If the winsock is already loaded then check if it is closed, it is closed then let the client use that one, and dont load a new one. If the winsock is already loaded but is open then move on to the next index. If the winsock isn't loaded then load it and let the client use it.

I hope this helps you.

thanks alot

Winsock is a trouble thing as sometime,somewhere!U need some 3th component to do it..That is the best way to reduce wrong..