How to pass a user defined type to an Api function?

[ATHUEL]

Hi all,
I´m facing this problem with an Api function:
the function is something like this in c++)

bool someFunction ( LPDest Dest, hFile HandleFile)

( translated to vb from c++)

public someFunction( ByRef DestinationPointer as Any, ByVal HandleToFile as long ) as boolean

the intendeed functionality according to the specification is as follow:

DestinationPointer: is a pointer to a structure ( or user defined type) that is filled by the function.

HandleToFile: handle to the file from where the data to fill the user defined type, is taken.

The function returns TRUE on success, False on error.

So what i´ve done so far is:

1- I create an UDT of the form

Public Type UDT
X as Double
Y as Double
Z as double
End Type


2- I create a reference to that UDT

Dim someUDT as UDT

3- Call the function as:
public someFunction( someUDT, HandleToFile ) as boolean

At this point all seems to work, exept that the values I get in someUDT.X , someUDT.Y and someUDT.Z makes no sense.

even more, if I run this function more than once, i get diferent results for every data.

And here is where i´m stocked.

I was reading various post related to using pointers in VB but I don´t understand how to apply it to this particular case.
So any help would be greatly appreciated.

 

[three57m]

Instead of posting > public someFunction( ByRef DestinationPointer as Any, ByVal HandleToFile as long ) as boolean
Could you post the actual function.