c - 通过定义向结构体添加元素

Question

我有一个问题。我正在尝试通过先前定义的常量添加结构元素。这是示例代码(OpenGL+WinAPI)

#define ENGINE_STRUCT \
    HGLRC       RenderingContext;\
    HDC         DeviceContext;

然后:

typedef struct SWINDOW {

    ENGINE_STRUCT

    HWND        Handle;
    HINSTANCE   Instance;
    CHAR*       ClassName;
    BOOL        Fullscreen;
    BOOL        Active;
    MSG         Message;
} WINDOW;

这可能吗？

Answer 1

是的，这是可能的，宏是一个简单的文本替换

http://www.cplusplus.com/doc/tutorial/preprocessor/

The preprocessor examines the code before actual compilation of code begins and resolves all these directives before any code is actually generated by regular statements.