Export dll method from C++ to C#. Why I need: “ extern ”C“ ”

Question

In my dll there is a method that I want to export.

//Works:

extern \"C\" __declspec(dllexport)

//Wont work

__declsp         


        

Answer 1

I have tried this with a function with 1 parameter and you have to use

[DllImportAttribute("whatever.Dll" ,CallingConvention = CallingConvention.Cdecl)]

for the import in C# to work. Stdcall statement only works (in the presented situation, not in general ) for functions with no parameters and that return void. Tested in vs2012 express edition.

As a side note, the dependency walker can be downloaded from http://www.dependencywalker.com/