C++ Offset function inside Class

[RandomUser]

Hello, thanks for reading, i usually use this method for accesing functions in executables, the code is executed from a DLL (always works, except when the function are inside of a class, even tho is public):

.h:

typedef int (*pgObjViewportClose) (OBJECTSTRUCT* gObj);
extern pgObjViewportClose gObjViewportClose;

.cpp

pgObjViewportClose gObjViewportClose = (pgObjViewportClose) 0x04F1940;

That works, but i can't get it to work if the accesing function is inside of a class, i get Unhandled Exception while trying to access a function inside a class, is there a way to do it?.

Thanks

[weaknessforcats]

You can't call functions inside of a class unless you have an object or the function is static.

class A
{
   public:
     void Mbr1();
     static Funct();
};

A obj;
  obj.Mbr1();  //OK
  A::Funct();  //OK. static functions don't require an object
  A::Mbr1();   //NOT OK. Won't compile.

Also you mention DLL. A DLL is a Microsoft C artifact where you use GetProcAddress and that requires you inhibit the mangler in C++ in order to find your function or you export the mangled name using a .def file.