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Merge Win32 c++ dll with managed c++ dll

I have a c++ project compiled with /clr support(e.g. wrapper.dll). This project(wrapper.dll) is a wrapper between .Net enviroment and unmaged dll(e.g. noCode.dll), which inherits from. I dont have access to code of inherited dll(noCode.dll), but I can link it to my wraper (by noCode.lib and noCode.h files).
When I want to use my wraper(wrapper.dll) in c# project I reference it and have to copy my unmanaged dll(noCode.dll) to location of c# project execution.
Is it possible to merge c++ unmamaged dll(noCode.dll) to managed dll(wrapper.dll) to allow to use only one file by reference(noCodeWrapper.dll) in c# projects?

It is not possible to link DLL files together.
But you can add that nocode.LIB to your DLL and then you don't need [DllImport]. Since you have LIB and H files, you can call the "nocode" functions directly from your managed C++ code.

If you had access to noCode.dll source code you could integrate it with wrapper.dll. Otherwise merging DLL binaries is not a task that could give predictable results.

C# Wrapper for C++ but compiles as static library only

I am trying to run un-managed native C++ class code from C# by writing a wrapper. My C++ code compiles as a static library (.lib) with no problems. The code depends on other code which, I believe, are all compiled as static libraries. I am not able to compile this as a DLL as there are linker errors.
I have just learnt that the wrapper needs to be compiled as a DLL so that it may be invoked from C#. Is this true? Can I not compile my wrapper as a static library to be used in C#?

C# cannot load .lib files.
P/Invoke can only load .DLL files (they don't have to be named .DLL but they have to be the right file format).

C++/CLI wrapper trying to use MFC CObject inheritance

Using VS2010, I am working on wrapping a large number of .h files and one .lib from native C++ (using MFC) to C++/CLI for eventual use as a referenced .dll in C#.
While creating the wrapper I'm getting compiler errors stating CObject is undefined. In the project properties I have set use of MFC to use MFC in a static library and runtime library to multi-threaded debug DLL (/MDd). I am linking the .lib and including the .h files. The compiler errors are in the .h files where some of the classes are inheriting from CObject.
Shouldn't the compiler know about CObject?

Are you #including the MFC headers? afx.h, afxwin.h, anything like that? It's possible that #include was in stdafx.h in your native C++ project, and didn't get copied into the header files that you're using in your C++/CLI project.

Accessing C# library from VC++ code

I have windows form application written in VC ++ . I want to change the button click in this app (WInform app in VC++) to hit a function written in C#.
What are the possible ways to do this.

Calling a C# assembly without compiling with C++/CLI is tricky. some of the ideas I've had:
a) Create a mixed-assembly wrapper dll (mixed assemblies contain both native code and managed code). Add a reference to your C# assembly, then create functions in your dll that call the C# code via C++/CLI, then define dll entrypoints ( __declspec(dllexport) ) for those functions. You can now link against the dll as it will provide a native interface that C++ can understand, while internally that dll can call your C# code.
( Afterthought: You can probably compile this to a .lib, that would be easier than a dll.)
Walkthrough: Creating and Using a Static Library
b) Use Mono to call the C# assembly. Mono has a C API which you can use to load and use managed assemblies without using c++/CLI. This is what I would do if C++/CLI is not an option.
Embedding Mono
c) If your function has a relatively simple input/output signature (no large objects, etc) you might consider compiling your C# function into an executable and use standard input/output to call the function. You'll have to carry input arguments and the output as text, though. Then make C++ start the executable and pass some input to it, and read the output.

dll export/import problem in visual studio 2010

I am wrote a visual c++ win32 console app, and i wrote it and tested it in
win32 console project
. then i switch to
win32 project
and imported all the source files and created a dll for it. by mark the class i want to export as
#define DllExport __declspec( dllexport )
class DllExport theClass {
}
it works and the dll is generated. then i created a another c# project and want to add the dll to the project. by reference->add reference-> browser. then i select that dll.
then it is gives me an error
a reference to the '''''''.dll could
not be added. please make sure that
the file is accessible, and that is a
valid assembly or com component.
anyone knows where i did wrong to generate/import the dll?
thanks

The Add Reference dialog can only work for DLLs that contain metadata (managed code) or a type library (a COM server). Your DLL doesn't fit that bill, you can only use the [DllImport] attribute in C# code to use the P/Invoke marshaller to call an unmanaged DLL entrypoint.
That can not be a native C++ class, like you are trying to do, there is no reliable mechanism for managed code to allocate unmanaged memory and call the constructor (and destructor) of a native C++ class. Short from the difficulty of finding the constructor and destructor code, there is no way for the P/Invoke marshaller to know the size of the object. The C++ language doesn't generate the metadata necessary to know this required information.
If you want to pursue P/Invoke then write an plain global function, decorated with extern "C", __declspec(dllexport) and (optionally) __stdcall.
If you want to export a C++ class then the only avenue is using the C++/CLI language and write a "ref class" wrapper for the native C++ class.
Or you could write a COM coclass, the universal glue in Windows. Very well supported by .NET, probably not something you want to pursue if you never wrote COM code before. ATL is the best way to get one going.