Subclassing problems [Resolved]

I'm trying to create a multi-threadedWinsock API application by making multiple calls to HookForm and UnHookForm that call SetWindowLong. I have 2 threads (forms) at the moment. The sockets are created and data is sent for both threads but 1/2 the time data is returned for only 1 of the threads. Is there something fundamental I'm doing wrong?

VBAhack

Thought maybe some code would help:

VB Code:

'In 1st form
Private Sub Form_Load()
    Dim sSave As String
    hwnd1 = Me.hwnd
    HookForm hwnd1, Me
    StartWinsock sSave
    lSocket1 = ConnectSock("finance.yahoo.com", 80, 0, Me.hwnd, False)
End Sub
 
Private Sub Form_Unload()
    closesocket lSocket1
    EndWinsock
    UnHookForm Me.hwnd
End Sub
 
'In 2nd form
Private Sub Form_Load()
    Dim sSave As String
    hwnd2 = Me.hwnd
    HookForm hwnd2, Me
    StartWinsock sSave
    lSocket2 = ConnectSock("finance.yahoo.com", 80, 0, Me.hwnd, False)
End Sub
 
Private Sub Form_Unload()
    closesocket lSocket2
    EndWinsock
    UnHookForm Me.hwnd
End Sub
 
'In a standard module.  Public variables Form1, Form2, lSocket1, lSocket2, hwnd1, hwnd2
Public Sub HookForm(ByVal hwnd As Long, f As Object)
    Select Case hwnd
        Case hwnd1: Set Form1 = f
        Case hwnd2: Set Form2 = f
    End Select
    PrevProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf WindowProc)
End Sub
 
Public Sub UnHookForm(ByVal hwnd As Long)
    If PrevProc <> 0 Then
        SetWindowLong hwnd, GWL_WNDPROC, PrevProc
        PrevProc = 0
    End If
End Sub
 
Public Function WindowProc(ByVal hwnd As Long, ByVal uMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
    If uMsg = WINSOCKMSG Then
        ProcessMessage wParam, lParam
    Else
        WindowProc = CallWindowProc(PrevProc, hwnd, uMsg, wParam, lParam)
    End If
End Function
 
Public Sub ProcessMessage(ByVal lFromSocket As Long, ByVal lParam As Long)
    Dim X As Long, ReadBuffer(1 To 1024) As Byte, strCommand As String
    Select Case lParam
        Case FD_CONNECT
        Case FD_WRITE
            Select Case lFromSocket
                Case lSocket1
                    strCommand = "GET /q?s=INTC HTTP/1.0" + vbCrLf
                    strCommand = strCommand + "Pragma: no-cache" + vbCrLf
                    strCommand = strCommand + "Accept: */*" + vbCrLf
                    strCommand = strCommand + "Accept: text/html" + vbCrLf + vbCrLf
                    SendData lFromSocket, strCommand
                Case lSocket2
                    strCommand = "GET /q?s=GE HTTP/1.0" + vbCrLf
                    strCommand = strCommand + "Pragma: no-cache" + vbCrLf
                    strCommand = strCommand + "Accept: */*" + vbCrLf
                    strCommand = strCommand + "Accept: text/html" + vbCrLf + vbCrLf
                    SendData lFromSocket, strCommand
            End Select
        Case FD_READ
            Select Case lFromSocket
                Case lSocket1
                    Do
                        X = recv(lFromSocket, ReadBuffer(1), 1024, 0)
                        If X > 0 Then
                            strData1 = strData1 + Left$(StrConv(ReadBuffer, vbUnicode), X)
                            Debug.Print X; " bytes read....." & lFromSocket
                        End If
                        If X <> 1024 Then Exit Do
                    Loop
                Case lSocket2
                    Do
                        X = recv(lFromSocket, ReadBuffer(1), 1024, 0)
                        If X > 0 Then
                            strData2 = strData2 + Left$(StrConv(ReadBuffer, vbUnicode), X)
                            Debug.Print X; " bytes read..............." & lFromSocket
                        End If
                        If X <> 1024 Then Exit Do
                    Loop
            End Select
        Case FD_CLOSE
            Select Case lFromSocket
                Case lSocket1
                    Unload Form1
                    Set Form1 = Nothing
                    Debug.Print strData1
                    strData1 = vbNullString
                Case lSocket2
                    Unload Form2
                    Set Form2 = Nothing
                    Debug.Print strData2
                    strData2 = vbNullString
            End Select
    End Select
End Sub

Connection occurs and data is sent in both cases, but only sometimes is data return for both (always for 1). Any suggestions? Thanks.

VBAhack

Forgot one bit:

VB Code:

'In standard module
Private Sub TryIt()
    Load Form1
    Load Form2
End Sub

VBAhack

Code:

---

PrevProc = SetWindowLong(hwnd, GWL_WNDPROC, AddressOf WindowProc)

---

You must store Long's against hWnd's and not in variables.

Set Form1 = f can be another problem ! Try to use CopyMemory.

Go to http://www.planetsourcecode.com/vb/s...57119&lngWId=1 and take a look at my code. Make the changes. It will work, i bealive.

Thanks for your reply. The main problem was that I was ending Winsock prematurely (each Form_Unload had a call to EndWinsock) . When I fixed that it worked but I still got an occasional crash that I never figured out, but my guess was that it had to do with passing forms as Objects. Anyway, I completely abandoned the approach of using forms and decided instead to use a single window (CreateWindowEx API) for subclassing and created multiple sockets attached to the window. I've been sucessfully in creating 52 simultaneous threads w/o any crashes.

VBAhack

Resolved.

VBAhack