【cocos2d-x 3.5】Lua与C++简单交互

（一）lua调用C

1)在VS工程中编写下面两个文件

①　Luatools.h

extern "C" {
#include"lua.h"
}
int cc_lua_log(lua_State *L);

②　Luatools.cpp

#include"LuaTools.h"
#include"cocos2d.h"
int cc_lua_log(lua_State *L){
cocos2d::log("Log : %s",lua_tostring(L,1));
return 1;
}

2)在VS的AppDelegate.cpp中做如下修改

①　引入头文件#include"LuaTools.h"

②　在applicationDidFinishLaunching方法中添加代码

LuaStack* stack = LuaEngine::getInstance()->getLuaStack();
lua_State *L = stack->getLuaState();
lua_register(L, "cc_lua_log", cc_lua_log);

注：这段代码要在 ScriptEngineManager::getInstance()->setScriptEngine(engine)前加入

3）在lua部分直接可以调用cc_lua_log()

（二）C调用lua

1）在Lua工程新建一个文件Test.lua

function add(x,y)
return x+y
end

2）C++端代码如下

lua_State* ls = lua_open();
const char *path = String::createWithFormat("%s", FileUtils::getInstance()->fullPathForFilename("Test.lua"))->getCString();
luaL_openlibs(ls);
int isOpen = luaL_dofile(ls, path);
lua_getglobal(ls, "add");
lua_pushnumber(ls, 100);
lua_pushnumber(ls, 120);
lua_call(ls, 2, 1);
int sum = (int)lua_tonumber(ls, -1);
lua_pop(ls, 1);
cocos2d::log("ok! lua return result is %d",sum);