Question

I am loading OCX dynamically in VB 6.0.

The following is the code that I am using to load and call the methods:

Private Declare Function FreeLibrary Lib "kernel32" (ByVal hLibModule As Long) As Long 
Private Declare Function LoadLibrary Lib "kernel32" Alias "LoadLibraryA" (ByVal lpLibFileName As String) As Long 
Private Declare Function GetProcAddress Lib "kernel32" (ByVal hModule As Long, ByVal lpProcName As String) As Long 
Private Declare Function CallWindowProc Lib "user32" Alias "CallWindowProcA" (ByVal lpPrevWndFunc As Long, ByVal hWnd As Long, ByVal Msg As Any, ByVal wParam As Any, ByVal lParam As Any) As Long 

Private Sub Foo 
  On Error Resume Next 

  Dim lb As Long, pa As Long 
  Dim versionString As String 
  Dim retValue as Long 

  lb = LoadLibrary("D:\projects\other\VB_DLLs\TestDLL\TestDLL.dll")   

  'retrieve the address of getVersion' 
  pa = GetProcAddress(lb, "getVersion") 

  'Call the getVersion function' 
  retValue = CallWindowProc (pa, Me.hWnd, "I want my version", ByVal 0&, ByVal 0&) 

  'release the library' 
  FreeLibrary lb 
End Sub 

Now I want to access public properties of OCX. How I can access (get/set) the properties of OCX?

Answer 1

You can not use an OCX/COM control in that manner.

To create and use an instance of the object, you will need to.. create an instance of the object, then use that.

Set TestObject = CreateObject("TestDll.TestObject")
Value = TestObject.Method(InputValue)

This requires the DLL to be registered, and will use whichever is registered rather than a specific instance.

If you don’t want it to be registered, look at DirectCOM.