Lua 与C/C++ 交互系列:注册枚举enum到Lua Code中

转自：http://blog.csdn.net/sunning9001/article/details/46659163

在Lua Code中注册C/C++的枚举非常容易,就像注册全局变量一样。我们使用枚举名称作为命名空间,来避免注册的枚举发生冲突。注册的枚举存储在全局环境(线程环境)中。

当在Lua Code中访问枚举时,通过名称来访问对应的值。

sample_9.cpp   c++代码如下：

 //在Lua Code中注册的enum,为了避免冲突,以名称作为enumTable来存储
 enum Week
 {
     Monday,
     Tuesday,
     Wednesday,
     Thursday,
     Friday,
     Saturday,
     Sunday,
 };
 //定义宏用来方便使用设置键值
 #define LUA_ENUM(L, val) \
   lua_pushliteral(L, #val); \
   lua_pushnumber(L, val); \
   lua_settable(L, -3)


 void register_enum(lua_State* L)
 {   //创建一个enumTable,用于存储Enum的所有枚举。通过枚举名称=枚举值
     lua_newtable(L);
     //设置 enumTable["Monday"]=Monday
     LUA_ENUM(L, Monday);
     LUA_ENUM(L, Tuesday);
     LUA_ENUM(L, Wednesday);
     LUA_ENUM(L, Thursday);
     LUA_ENUM(L, Friday);
     LUA_ENUM(L, Saturday);
     LUA_ENUM(L, Sunday);
     //把enumTable存在在_G 全局环境(线程环境)中,以枚举名称作为键
     lua_setglobal(L,"Week");
 }
 int main(int argc, char *argv[])
 {
     lua_State* L = lua_open();
     luaL_openlibs(L);
     register_enum(L);
     luaL_dofile(L, "sample_9.lua");
     lua_close(L);
     return 0;
 }

sample_9.lua   Lua Code代码如下：

 local Week=_G["Week"]
 print(Week)
 print(Week.Monday)
 print(Week.Tuesday)
 print(Week.Wednesday)
 print(Week.Thursday)
 print(Week.Friday)
 print(Week.Saturday)
 print(Week.Sunday)

输出结果：