[C++] DLL - extern "C" and class objects

[vivendi]

I want to create a dll in C++ (NOT MFC) in a way so that others can use the functionality that i've build in my dll. So with other words, when someone is programming C#, he should be able to add my DLL as reference and have access to the functions of that dll.

Now i've read a topic about that here on how to do that:
http://www.codeguru.com/forum/showthread.php?t=231254

So all i have to do according to that post is declare my functions as extern "C" and create a DEF file. But i have a question about using extern "C".


I have a main.cpp file in my dll which has the folliwing main code:

BOOL WINAPI DllMain(HINSTANCE hInstance,DWORD fwdReason, LPVOID lpvReserved)
{
	switch(fwdReason)
	{
		case DLL_PROCESS_ATTACH:
			break;
		case DLL_THREAD_ATTACH:
			break;
		case DLL_PROCESS_DETACH:
			break;
		case DLL_THREAD_DETACH:
			break;
	}
	return(TRUE);	// The initialization was successful, a FALSE will abort
			// the DLL attach
}

I also have to other files, test.h and test.cpp. The headerfile contains the structure of my class:

class cTest
{
public:
void MyFunc ( );
}

and the sourcefile has the logic of my class:

void cTest::MyFunc ( )
{
    MessageBox ( NULL, "The test worked!", "Test", MB_OK );
}

So my question now is, how do i use extern "C" in my case?? What i want is when others use my DLL is that they have access to my classes. So that they can simply say something like this in their application:

cTest test = new cTest();
test.MyFunc();

Do i just encapsulate my entire class in a extern "C" block?? like so:

extern "C"
{
   //my entire class
   //comes in here
}

Or can i only use structs in this case??

Well, i really hope someone here can help me out with my questions

Thanks for any help!