Question

i want use dll made in c#(visual studio 2008) in c++ project(visual studio 2003). how to do that ? please heeelp

Answer 1

There is more than just COM interop, the MSDN FAQ also lists lesser known methods:

2.2 How do I call .NET assembly from native Visual C++?

There are basically four methods to
call .NET assembly from native VC++
code. Microsoft All-In-One Code Framework has working examples that
demonstrate the methods.

1. Native VC++ module calls CLR Hosting APIs to host CLR, load and
   call the .NET assembly. (All-In-One
   Code Framework Sample Code:
   CppHostCLR)

2. If the .NET assembly can be exposed as a COM component, native
   VC++ module can call into the .NET
   assembly through .NET – COM interop.
   (All-In-One Code Framework Sample
   Code: CppCOMClient)

3. Reverse PInvoke: the managed code call native passing a delegate
   the native code can call back.
   (All-In-One Code Framework Sample
   Code: CSPInvokeDll)

4. If the module containing native VC++ code is allowed to enable CLR, the native VC++ code can call
   .NET assembly directly through the “It
   Just Works”, or “IJW”, mechanism. (All-In-One Code Framework Sample Code: CppCLIWrapLib)