Class name conflicts in C# and managed C++ dll in VS 2003

ken du

I created a project in .net 2003. In this project, the c# code will call a managed dll which is built by C++. In the dll, it defines some classes whose names conflict with the classes from .net framework. For example: Stream, Array, in C++ dll and System.IO.Stream, System.Collections.Array in C#. So, when i compile the project, all the c# code must include the namespace like System.IO.Stream. It is grotty and it is more important that the c# code has been written before the C++ dll and it means enormous and boring work to change the c# code. I have tried to find and set the corresponding compile options to overcome this problem. But nothing works. Please help me and any suggestions are appreciated!

8 Replies

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Alan19y ago
It hadn't occured to me that it might be a 'mixed mode' Managed C++ dll.

Anyway, I'm pleased that you've solved it now :-)
ken du19y ago
Thanks for your help. I have solved the problem from the msdn. http://support.microsoft.com/?scid=kb%3Ben-us%3B822330&x=13&y=12 Adding the compiler option "/d1PrivateNativeTypes" in vs 2003 is ok. Best regards.
ken du19y ago
I have read some topics about the "class visibility" in MSDN. The default visibility for a class is private, which means that it is visible only within the assembly. But "Array" is a unmanaged class, how to control its visibility to the outside?
ken du19y ago
The code in c++ is just like the following : public __gc class OutClass { Array arr; ... } class Array { } Array is an internal class while OutClass is a public class. I only want to expose "OutClass" to the c# code but not "Array". Since "Array" is not defined by the keyword "__gc", why is it still exposed to the outside c#? How can i hide the "Array" by recompiling the c++ dll ? Thanks a lot!
ken du19y ago
Thanks for your quick and good answers. The way you adviced is useful. But I have another question that all the conflict classes in C++ dll will not be used in c# code. Could I define all the conflict classes as "internal" classes which will not seen by the c# code? I can access the c++ code. Thanks in advance.
Alan19y ago
Sorry but, to the best of my knowledge, there are no compiler options in VS 2003 which would help with this problem.

However, if you have access to the Managed C++ source code, then you could simply place everything within a namespace (CPPTypes say) and rebuild the dll.

Them, from the C# side, you could use some 'using' aliases to distinguish between the similarly named types. For example:

using System.IO;
using System.Collections;
using CPPTypes;
using Stream = System.IO.Stream;
using CPPStream = CPPTypes.Stream;
using Array = System.Array;
using CPPArray = CPPTypes.Array;

That way you wouldn't need to fully qualify the .NET framework Stream, Array etc from your code.
ken du19y ago
The classes in C++ are defined in a global level. Is there any other way like setting compiler options in the c++ project or c# project? Because it succeeds in vs 2005 with some different compiler options which are not supported in vs 2003. Thanks in advance.
Alan19y ago
Are the managed C++ classes themselves within a namespace or were they all defined at global level?