这个定义指令语法是什么意思？

Question

这些指令是代码和工作的一部分。但我不明白他们的语法。我只知道＆＃34; \＆＃34;表示代码继续下一行。有谁能够帮我？为什么会有＆＃34 ;;＆＃34;。什么＆＃34; ADDPOPUPMENU＆＃34;意思是什么大写？

#define ADDPOPUPMENU(hmenu, string) \
HMENU hSubMenu = CreatePopupMenu(); \
AppendMenu(hmenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, string);
// Add a menu item
#define ADDMENUITEM(hmenu, ID, string) \
AppendMenu(hSubMenu, MF_STRING, ID, string);

Answer 1

代码定义了两个独立的宏：

#define ADDPOPUPMENU(hmenu, string) \
HMENU hSubMenu = CreatePopupMenu(); \
AppendMenu(hmenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, string);

// Add a menu item
#define ADDMENUITEM(hmenu, ID, string) \
AppendMenu(hSubMenu, MF_STRING, ID, string);

预处理器#define语句只是定义文本替换。所以这样的代码：

ADDPOPUPMENU(MyMenu, "Name")
ADDMENUITEM(MyMenu, MyID, "Item")

在编译阶段开始之前的预处理阶段将替换为以下内容：

HMENU hSubMenu = CreatePopupMenu();
AppendMenu(MyMenu, MF_STRING | MF_POPUP, (UINT)hSubMenu, "Name");
AppendMenu(hSubMenu, MF_STRING, MyID, "Item");