Returning a string* as a result in WndProc

25 Mar 2005 3:35 PM

Kurt

I have a C++ dialog that is sending a message to my C# window and I need to
pass a string* back in the result of the message. On the C++ side this result
is cast as a CString*. How do I create this string on the C# side and convert
it to an IntPtr? My first guess is to allocate memory and copy the string to
it and then let the C++ app clean it up.

Thanks
Kurt

25 Mar 2005 4:26 PM

Mattias Sjögren

>How do I create this string on the C# side and convert
>it to an IntPtr? My first guess is to allocate memory and copy the string to
>it and then let the C++ app clean it up.

Sure that will work, and you can do it with one of the
Marshal.StringTo* methods.

Mattias

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25 Mar 2005 5:27 PM

Kurt

Ok I'm using StringToHGlobalAnsi and the string I get on the other side is
blank.

Here is my code on the C++ side.

CString p((char*)lResult);

Show quote

"Mattias SjÃ¶gren" wrote:

> >How do I create this string on the C# side and convert
> >it to an IntPtr? My first guess is to allocate memory and copy the string to
> >it and then let the C++ app clean it up.
>
> Sure that will work, and you can do it with one of the
> Marshal.StringTo* methods.
>
>
>
>
> Mattias
>
> --
> Mattias SjÃ¶gren [MVP] mattias @ mvps.org
> http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
> Please reply only to the newsgroup.
>

29 Mar 2005 10:03 AM

Mattias Sjögren

>Ok I'm using StringToHGlobalAnsi and the string I get on the other side is
>blank.
>
>Here is my code on the C++ side.
>
>CString p((char*)lResult);

You're gonna have to show more of your code.

Mattias

--
Mattias Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.

29 Mar 2005 1:19 PM

Kurt

Thanks Mattias I figured it out.

Show quote

"Mattias SjÃ¶gren" wrote:

>
> >Ok I'm using StringToHGlobalAnsi and the string I get on the other side is
> >blank.
> >
> >Here is my code on the C++ side.
> >
> >CString p((char*)lResult);
>
>
> You're gonna have to show more of your code.
>
>
>
> Mattias
>
> --
> Mattias SjÃ¶gren [MVP] mattias @ mvps.org
> http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
> Please reply only to the newsgroup.
>