lua調用windows api或dll庫

1.問題或需求描述：
lua 調用 windows api 或 dll 庫
2.測試環境：
Lua 5.1.5
win7 32
3.解決方法或原理：

--引入 alien 庫
require("alien")

--加載庫文件
user32 = alien.load("user32.dll")

--函數聲明
user32.GetClassNameA:types("int", "long", "pointer", "int")
user32.EnumWindows:types("int","callback", "uint")
user32.MessageBoxA:types("int", "long", "string", "string", "uint")
user32.FindWindowA:types("long", "string", "string")
user32.PostMessageA:types("int", "long", "uint", "uint", "uint")

local function EnumWnd(hwnd, lParam)

    local buff = alien.buffer(64)
    user32.GetClassNameA(hwnd, buff, 63)
    print(tostring(buff))

    return 1
end

local EnumWndFunc = alien.callback(EnumWnd, "int", "long", "long")

result = user32.MessageBoxA(0, "演示：關閉計算器",  "請求確認", 0x00000004 + 0x00000020 + 0x00000100)
print("用戶響應鍵:" .. result)
if result == 6 then
    hwnd = user32.FindWindowA("CalcFrame", "計算器")
    if hwnd ~= 0 then
        user32.PostMessageA(hwnd, 0x0010, 0, 0) --WM_CLOSE
    end
end

result = user32.MessageBoxA(0, "演示：枚舉所有窗口類名",  "請求確認", 0x00000004 + 0x00000020 + 0x00000100)
print("用戶響應鍵:" .. result)
if result == 6 then
    user32.EnumWindows(EnumWndFunc,0)
end