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Returning a string* as a result in WndProc

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
Nov 17 '05 #1
4 1640
>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 Sjögren [MVP] mattias @ mvps.org
http://www.msjogren.net/dotnet/ | http://www.dotnetinterop.com
Please reply only to the newsgroup.
Nov 17 '05 #2
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);

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

Nov 17 '05 #3
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.
Nov 17 '05 #4
Thanks Mattias I figured it out.

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

Nov 17 '05 #5

This thread has been closed and replies have been disabled. Please start a new discussion.

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