(Lua) C++ 寫函式，Lua 呼叫使用

C++ 裡頭寫一個 Function 但是透過 Lua 提供input參數並且回傳結果給Lua 輸出的辦法。

Lua 檔案

 local ave, sum = average(, , )
 print("ave : ", ave, "sum = ", sum)

C++ 檔案

 int average(lua_State *L){

     int lua_args_count = lua_gettop(L);

     lua_Number sum = ;
     for (int i = ; i < lua_args_count; i++){
         sum += lua_tonumber(L, i);
     }

     lua_pushnumber(L, sum / lua_args_count); // follow order to return value ave
     lua_pushnumber(L, sum); // sum

     // return 2 number to Lua
     return ;
 }

 int main(int argc, const char *argv[])
 {
     //cout << "lua test platform!!!" << endl;
     string scriptnema = "main.lua";
     string script_char = "print('123')";

     int luaError;
     lua_State *L = luaL_newstate();
     if (L == NULL)
     {
         cout << "luaL_newstate faile !!!" << endl;
         return -;
     }
     luaL_openlibs(L);
     lua_register(L, "average", average); // "average" --> Lua symbol call C++ function method (local ave, sum = average(11, 20, 63))

     luaError = luaL_dofile(L, scriptnema.c_str());
     lua_close(L);
     system("pause");
     return ;
 }

第31行，這邊主要是讓Lua symbol 可以辨識 average的感覺，還有另一種辦法可以自己創造一個

自己的Lua環境(Lib)，打算在下一篇紀錄下來。

// "average" --> Lua symbol call C++ function method (local ave, sum = average(11, 20, 63))
lua_register(L, "average", average);