在C ++中使用ac＃dll

Question

I am trying to use ac# dll in c++. I developed ac# dll.

I tried to add it as a reference to a c++ file, it showed warning as

Could not add a reference
- Targets a higher version of .NET Framework
- Not a .Net assembly
- Not a registered ActiveX control

so I added the dll like as follows in my c++wrapper file. I could able to access the classes present in the c# dll.

#using <C:\Users\New\Documents\Visual Studio 2015\Projects\ClassLibrary1\ClassLibrary1\bin\Debug\ClassLibrary1.dll>
using namespace csharp; //namespace in which managed class is present
#include "Header.h"
extern "C"
{
    __declspec(dllexport)  int func()
    {
        managedClass^ r = gcnew managedClass();
        someClass^s = gcnew someClass();
        s->name = "xyz";
        return r->getString(s);
    }
} 

Then I imported the wrapper dll to c++ console application as follows

#include <iostream>
#include <Windows.h>
#pragma comment(lib,"C:\\Users\\New\\Documents\\Visual Studio 2015\\Projects\\C++Wrapper\\Debug\\C++Wrapper.lib")
#include <C:\Users\New\Documents\Visual Studio 2015\Projects\C++Wrapper\C++Wrapper\Header.h>
void main()
{

    int result = func();
    std::cout << result;
    getchar();
}

But I am getting error as follows:

Unhandled exception at 0x7479D928 (KernelBase.dll) in C++ClientPro.exe: 0xE0434352 (parameters: 0x80070002, 0x00000000, 0x00000000, 0x00000000, 0x73790000).

I am getting the same error when I am trying to load the dll using LoadLibrary(libpath) function.
When I searched for this error, I got to know that It could not able to locate the file. In which step I was wrong. What I have to correct to use the c# dll in c++?
Edit
1) I've edited my c++wrapper file. I want to create an instance for a class in c# dll and also pass it as a function parameter to the same dll.
That's why I did not go for another method in which we could export only the functions using public interface, we could not able to access the classes.
2) I enabled /clr in my projects.

Answer 1

1) Use CCW (Com Callable Wraper). To mark your managed(c#) assembly with "Register for COM interop" please follow below steps

Step 1. With a project selected in Solution Explorer, on the Project menu, click Properties. Step 2. Click the Compile tab in Visual Basic. Click the Build tab in C#. Step 3. Select the Register for COM interop check box.

else you can visit

a) http://msdn.microsoft.com/en-us/library/ms404285.aspx

For more details on "How to call a managed DLL from native Visual C++ code

For example see here

http://www.codeproject.com/Articles/16206/Call-C-code-from-C-and-read-an-array-of-struct-whi

2) Use Reverse P/Invoke as shown below

http://tigerang.blogspot.in/2008/09/reverse-pinvoke.html

when you use Reverse P/Invoke be careful for marshalling of parameters.