MFC DLL

//afxv_dll.h

#ifndef AFX_EXT_DATA
    #ifdef _AFXEXT
        #define AFX_EXT_CLASS       AFX_CLASS_EXPORT
        #define AFX_EXT_API         AFX_API_EXPORT
        #define AFX_EXT_DATA        AFX_DATA_EXPORT
        #define AFX_EXT_DATADEF
    #else
        #define AFX_EXT_CLASS       AFX_CLASS_IMPORT
        #define AFX_EXT_API         AFX_API_IMPORT
        #define AFX_EXT_DATA        AFX_DATA_IMPORT
        #define AFX_EXT_DATADEF
    #endif
#endif