How to use a class in DLL?

Question

Can I put a class inside a DLL? The class i wrote is this:

    class SDLConsole
{
      public:
             SDLConsole();
             ~SDLConsole(){};
             


        

Answer 1

If you want to expose the data in a class, the above solutions won't cut it. You have to slap a __declspec(dllexport) on the class itself in the DLL compilation, and a __declspec(dllimport) in the module that links to the DLL.

A common technique is to do this (Microsoft wizards produce code like this):

#ifdef EXPORT_API
#define MY_API __declspec(dllexport)
#else
#define MY_API __declspec(dllimport)
#endif

class MY_API MyClass {
   ...
};

Then make sure EXPORT_API is defined in the DLL project, and make sure it isn't defined in the module that links to the DLL.

If you create a new DLL project in Visual C++ from scratch, and check the check box "Export symbols", some sample code will be generated using this technique.