DllImport

[Zoltan]

OS : Windows XP Professional
Environment : MS Visual Studio 2005
Language : C#

I am trying to call an unmanaged function that is in a dll written in
C++. I did call the unmanaged fucntions already and i know almost
everything. My problem is that i do not have those datatypes under C#
that i had under C++. For example :

DWORD etCreateTalker (
LPCTSTR lpszReaderName,
LPHTALKER phTalker,
DWORD dwFlags
);

Neither LPCTSTR nor LPHTALKER are referencable from C#. If i put a
simple string instead of these types the function will be called
without a single error, but then i do not know the information because
of inproper casting, for example, instead of color, i get a 2 digit
number.....

To my best, the best would be if i re-declare these datatypes under C#
so i will have proper casting ?! Or could i import "3rd party"
datatypes from the dll into C# ?

I have put a similar question on the web before and i was told what is
what and so this would be my last question to make this work. Microsoft
advised me a book on API/COM but i hope that i don't need to read an
arm thick book to complete the answer.

Any help is greatly appreciated.

Zoltan.

 

[SirMike]

Dnia 17 Nov 2006 07:06:24 -0800, Zoltan napisa³(a):

DWORD etCreateTalker (
LPCTSTR lpszReaderName,
LPHTALKER phTalker,
DWORD dwFlags
);

DWORD is just simple value type.
Look in windef.h and everything will be clear.

typedef unsigned long DWORD;

LPCTSTR is a pointer to the String.

 

[SirMike]

Look also at this article - it will explain a lot.

http://www.codeproject.com/csharp/essentialpinvoke.asp

 

[Otis Mukinfus]

Look also at this article - it will explain a lot.

http://www.codeproject.com/csharp/essentialpinvoke.asp

Thanks for the link, Mike. Good stuff.


Good luck with your project,

Otis Mukinfus
http://www.arltex.com
http://www.tomchilders.com

 

[Zoltan]

Thank you !
Zoltan.

Otis Mukinfus írta:

Thanks for the link, Mike. Good stuff.


Good luck with your project,

Otis Mukinfus
http://www.arltex.com
http://www.tomchilders.com