lua语法四table表

发布时间 2024-01-07 15:38:15作者: 孙龙-程序员

一)table (表)
Table 类型实现了一种抽象的“关联数组”。即可用作数组,也可以用作map。
lua中没有数组和map,都是用table这个类型

--数组
java int[] intArr = new int[]{1,2,3,4,5,6};
intArr[0]
intArr[1]
--map----> key value

HashMap map
map.add(key,value)

-- 初始化表
mytable = {}

-- 指定值
mytable[1]= "Lua"
mytable[2]= "Lua2"
mytalbe["k1"] = v1;

-- 移除引用
mytable = nil
-- lua 垃圾回收会释放内存

lua类似数组的table ,索引值从1开始,,而不是0

mytable={1,2,3,4,5}
mytalbe[1]

mytable={"a","b","hello","world"}

print(mytable[1],mytable[2],mytable[3],mytable[4]);//output:a,b,hello,world
print("------------------")

mytable1 = {key1 = "v1",k2="v2",k3="v3"}

print(mytable1["key1"],mytable1["k2"],mytable1["k3"]);//output:v1,v2,v3
print("------------------")

mytable2 = {"a",key1 = "v1","b",k2="v2",k3="v3","hello","world"}
等价于:
mytable2 = {1="a",key1 = "v1",2="b",k2="v2",k3="v3",3="hello",4="world"}
print(mytable2[1],mytable2["key1"],mytable2[2],mytable2["k2"],mytable2[3],mytable2[4]);
//output:a,v1,b,v2,hello,world

talbe key可以为 number 或字符串,,也可以是其他类型

table 是内存地址 赋值给变量


二)table进行赋值给变量,其实是把内存地址给了变量,变量只是引用了内存地址

 

local mytable1 = {"a",key1 = "v1","b",k2="v2",k3="v3","hello","world"}

local mytable2 = mytable1

mytable2[1] = "aa"

print(mytable2[1])//aa

print(mytable1[1])//aa


mytable2 = nil --移除的是引用

print("-------------")
print(mytable1[1])//a

内存指针--》C++