CopyMemory issue (WM_SETTEXT problem - ADVANCED) (SOLVED but still in Brainstorming)

[Axonn]

Hi everybody. I previously had some issues with WM_SETTEXT that are now fixed, thanks to some great help around here : ). I still have one more problem related to this though.... The problem is the CopyMemory function.

I don't know how exactly can I retrieve from memory the text that I receive with the WM_SETTEXT message. I send this message from a VC++ Application. If I send a short message (under 10 characters or so) it works. If I send a really long message (more than 50 characters), the below code crashes.

I think that "Len(lParam)" is not correct. Logically, that's a LONG so Len will always return 4 I guess. So how can I know how much memory to copy? It's a kind of recursive problem: I can't know how much memory to copy unless if I copy it and I can't copy it because I don't know how much to copy : |.

Anybody got an idea about this?

Public Function TheSubclassedWndProc(ByVal hWnd As Long, ByVal uMsg As Long, ByVal wParam As Long, ByVal lParam As Long) As Long
 
Dim sString As String
 
    If uMsg = WM_SETTEXT Then
        CopyMemory sString, lParam, Len(lParam)
        MsgBox sString, vbInformation + vbSystemModal, "Trying to get the value"
        Exit Function
    End If
    
   TheSubclassedWndProc= CallWindowProc(loOriginalWindowProcedureAddress, hWnd, uMsg, wParam, lParam)
End Function

Thank you for reading anyway! : D.