UDT pointer

[deltarho[1859]]

I am trying to port some Drag&Drop code from PowerBASIC.

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Type DragDropType
  Title As zString * 20
  hHandle As Dword
End Type

In WndProc I have

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Static DragDrop As DragDropType
Dim ptrDragDrop As DragDropType Ptr = @DragDrop
DragDrop.Title = "Drag and Drop"
DragDrop.hHandle = Cast(Dword, hWnd )

and ptrDragDrop is getting passed like this

............., Cast( Dword_Ptr, ptrDragDrop ) )

In the Drag&Drop function ptrDragDrop is coming in via RefData.

Compilation-wise I cannot get past the hDlg statement. I have tried everything that I can think of and this is my latest attempt.

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............., RefData As Dword_Ptr ) As Winbool
Dim Dummy as Uinteger Ptr
 
Dummy = Cast( Uinteger Ptr, RefData )
hDlg = Dummy->hHandle

In PowerBASIC I simply have this.

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.................., ByVal RefData As DragDropType Ptr) As Long
 
hDlg = @RefData.hHandle

[fxm]

In PowerBASIC I simply have this.

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.................., ByVal RefData As DragDropType Ptr) As Long
 
hDlg = @RefData.hHandle

In FreeBASIC:

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.................., ByVal RefData As DragDropType Ptr) As Long
 
hDlg = RefData->hHandle

or:

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.................., ByVal RefData As DragDropType Ptr) As Long
 
hDlg = (*RefData).hHandle

[deltarho[1859]]

Thanks fxm. If only life was that simple. The problem is RefData is coming into the Drag&Drop function via Dword_Ptr and so is either a Ulong in 32 bit or Ulongint in 64 bit and why I used Uinteger in my attempt to convert RefData into a pointer. The value of RefData is a pointer but it is converted to a Dword_ptr before going to the Drag&Drop function so as to adhere to both the bi and MSDN. It is the last parameter of the Windows API SetWindowSubclass.

[sancho3]

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Dummy = Cast( Uinteger Ptr, RefData )
hDlg = Dummy->hHandle

Dummy is a UInteger pointer so it doesn't have a hHandle to retreive.

You say you tried lots of variations so this is one you probably already have tried but...
Can you not cast RefData straight to DragDropType ptr?

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hDlg = Cast(DragDropType ptr, RefData)->hHandle

Its also worth checking to see that RefData is the pointer you think it is at that point.

[deltarho[1859]]

That worked sancho3.

I did not try DragDropType ptr because I didn't think the Drag&Drop function would know what that was being defined in WndProc.

The problem coming from PowerBASIC is that there is no distinction between a scalar and a pointer - they are both 32 bit values and it is our responsibility as to how to use the value in question.

Thank you.