[Lua]lua初识

-- mac 上有很多文本编辑器，Himi找了很多，感觉TextMate是比较好用的，小巧且功能强大！而且免费,图标是个小菊花 - -

-- 注释语句

 

--[[ 

注释段落语句

  ]]--

 

--引用其他lua文件,不需要加上（.lua）后缀

--require "xx"

 

--变量不需要定义，可以直接赋值

count = 100  --成员变量

local count =100  --局部变量

 

--方法定义

function hello(...)

    --打印

    print("Hello Lua!");

    print(string.format(...))

end

 

-- 每一行代码不需要使用分隔符，当然也可以加上

-- 访问没有初始化的变量，lua默认返回nil

 

-- 调用函数形式

hello("你懂的")

 

--打印变量的类型

isOK =false

print(type(isOK))

 

-- 基本变量类型

a =nil --Lua 中值为nil 相当于删除

b =10

c =10.4

d =false

--定义字符串，单引号，双引号都可以的

e ="i am"

d ='himi'

 

--两个字符串的连接可以如下形式

stringA ="Hi"

stringB ="mi"

print(stringA..stringB)

 

--另外Lua也支持转移字符，如下

print(stringA.."\n"..stringB);

 

--修改字符串的部分gsub，可以如下形式:(将stringA字符串中的Hi修改为WT)

stringA=string.gsub(stringA,"Hi","WT")

print(stringA);

 

--将字符换成数字tonumber(不转也会自动转)

--将数字换成字符tostring(不转也会自动转)

stringC = "100"

stringC = tonumber(stringC)

stringC = stringC +20

stringC = tostring(stringC)

print(stringC)

 

--取一个字符串的长度使用 #

print(#stringC)

 

--创建 表

tableA ={}

m = "x"

tableA[m] =100

m2 ='y'

tableA[m2] =200

print(tableA["x"].."\n"..tableA.y)

--另外表还可以如下形式（从1开始）

tableB ={"4","5","6","7","8"}

print(tableB[1])

 

--算术操作符

c1 = 10+2

c2 = 10-2

c3 = 10*2

c4 = 10/2

c5 = 10^2

c6 = 10%2

c7 = -10+2

print(c1.."_"..c2.."_"..c3.."_"..c4.."_"..c5.."_"..c6.."_"..c7)

 

--控制操作

--if then elseif then else end

abc =10

if  abc ==10 then

    print("v1")

elseif abc == 9 then

    print("v2")

else

    print("v3")

end

 

--for

--从4（第一个参数）涨到10（第二个参数），每次增长以2（第三个参数）为单位

for i=4,10,2 do

    print("for1:"..i+1)

end

--也可以不制定最后一个参数，默认1的增长速度

for i=4,10 do

    print("for2:"..i+1)

end

 

tableFor = {"himi1","himi2","himi3","himi4","himi5"}

for k,v in pairs(tableFor) do

    print("for3:key:"..k.."value:"..v)

end

 

--while

w1 = 20

while true do

    w1=w1+1

    if w1 ==25 then

        break

    end

end

print("whlile:"..w1)

 

--repeat

    aa =20

    repeat aa = aa+2

        print("repeat:"..aa)

    until aa>28

 

--关系操作符

--需要注意的是不等于符号 ~=  而不是!=

ax =10

bx =20

 

if ax >bx then

    print("GX1")

elseif ax<bx then

    print("GX2")

elseif ax>=bx then

    print("GX3")

elseif ax<=bx then

    print("GX4")

elseif ax==bx then

    print("GX5")

elseif ax~=bx then

    print("GX6")

else

    print("GX7")

end

关于函数

--函数详解

 

--有一个返回值的函数

function funTestBackOne(aCount)

    local aCount= aCount+1

    return aCount

end

 

a =20

print(funTestBackOne(a))

 

--有多个返回值的函数

function funTestBackMore()

    return 2,3

end

 

a,b =funTestBackMore()

print(a.." and "..b)

 

--有变长参数的函数

function funTestUnKnow( ... )

    print(...)

end

funTestUnKnow(a,b,"Himi")

 

--闭合函数(一个函数写在另外一个函数内)

function funTest1( ... )

    local d = 12;

    d=d+...

    function funTest2( ... )

        print(d)

    end

    funTest2()

end

 

funTest1(100)

day1

--[[function fuc(n)

if n==0 then
return 1
else
return n*fuc(n-1)
end
end

print("input a number")
a = io.read("*number")
print(fuc(a))
--]]

--替换字符串
--[[
a = "one thing"
b = string.gsub(a,"one","two")
print(a)
print(b)
--]]

--转换数字
--[[
line = io.read()
n = tonumber(line)
if n==nil then
error(line.."is not a valid number")
else
print(n*2)
end
--]]

 

--拼接字符串
--[[
print("10"+1)

print("hell".."o")
--]]

--转换
--[[
line = io.read()
n = tonumber(line)
print(n)

print("我是一个字符串"..tostring(n))

print("10"=="10")
print(tostring(10)=="10")
--]]

--#计算长度
--[[
a = "hello"
print(#a)
print(#"good\0byte")
]]--

--table的使用
--[[
a = {}
k = "x"
a[k] = 10
a[20] = "great"
print(a[k])
print(a[20])
k = 20
print(a[k])
a["x"] =a["x"]+1
print(a["x"])

--使用同一个table
a = {}
a["x"] = 10
b = a --a和b使用了同一个table
print(b["x"])
b["x"] = 20
print(a["x"])
a = nil --b还在用table
b = nil --没人用table了

--自动增长
a = {}
--创建1000个新条目
for i = 1,1000 do a[i] = i*2 end
print(a[9])
a["x"] = 10
print(a["x"])
print(a["y"])
a.x = 20
print(a["x"])
print(a.x)

--循环存储值
a = {}
for i = 1,10
do a[i] = io.read() end

--输入打印数组的值
for i = 1,#a do
print(a[i])
end
--输出最后一个值
print(a[#a])
a[#a] = nil --删除最后一个值
a[#a + 1] = v --将v添加到列表的末尾
--]]

--[[
a = {}
a[1000] = 10
a[10000] = 11
print(table.maxn(a))

a = {}
i = 10;j = "10";k = "+10"
a[i] = "one value"
a[j] = "another value"
a[k] = "yet another value"
print(a[i])
print(a[j])
print(a[k])
print(a[tonumber(j)])
print(a[tonumber(k)])
--]]

--取小数点后面几位
--[[
x = math.pi
print(x%0.1)
print(x - x%0.01)

local tolerance = 10
function isturnback(angle)
angle = angle%360
return (math.abs(angle-180)<tolerance)
end
print(isturnback(-180))
--]]

--[[
a = 10
b = "10"
if tostring(a)~=b then print("不等")
else
print("相等")
end
--]]

--[[
a = {}
a.x = 1
a.y = 2
b = {}
b.x = 1
b.y = 2
c = a --a 等于 c table只有两个变量引用同一个的时候才是相等的
if a==b then print("a==b")
else
print("a~=b")
end
--]]

--[[

days = {"Sunday","Monday","Tuesday","Wednessday","Thursday","Friday","Saturday"}
print(days[1]) --这里注意不是从0开始

--a={x = 10,y = 20} <=>a = {};a.x = 10;a.y = 20

w = {x = 0,y = 0, label = "console"}
x = {math.sin(0),math.sin(1),math.sin(2)}
w[1] = "anther field"
x.f = w
print(w["x"])
print(w[1])
print(x.f[1])
w.x = nil
--]]

--[[
list = nil
for line in io.lines() do
list = {next = list,value = line}
end

local l = list
while l do
print(l.value)
l = l.next
end
--]]

--error("inva operation")

--相当于do while
--[[
repeat
line = io.read()
until line ~=""
print(line)

for i = 1,math.huge do --math.huge 无限大
print(1)
end
--]]

 

--[[
days = {"Sunday","Monday","Tuesday","Wednessday","Thursday","Friday","Saturday"}

revDays = {["Sunday"] = 1,["Monday"] = 2,["Tuesday"] = 3,["Wednessday"] = 4,["Thursday"] = 5,["Friday"] = 6,["Saturday"] = 7}
x = "Tuesday"
--print(revDays[x])

table.sort(revDays)
revDays1 = {}
for k,v in pairs(revDays) do --给v赋值“Sunday","Monday"... k赋值1，2...
print(k)
print(v)
end

--数组排序
a = {1,3,2}
table.sort(a)
for i,v in pairs(a) do print(v) end

--]]

--print("Monday是第"..revDays1["Monday"].."天")

--[[
for key,value in ipairs(revDays1) do
print(revDays1[key])
end
--]]

--[[
a = {}
a[1] = 10
a[2] = 20
a[3] = 30
for i,v in pairs(a) do print(v) end
--]]

 

 

day2

--函数
--数组求和

--[[
function sum(a)
local sum = 0
for i,v in pairs(a) do
sum = sum + v
end
return sum
end

a = {1,2,3,4,5,6}
num = sum(a)
print(num)

s,e = string.find("hello lua","lua")
print(s,e) --返回函数的开始结束字符，从1开始

--]]

--返回多个返回值
--[[
function maximum(a)
local mi = 1
local m = a[mi]
for i,val in pairs(a) do
if val> m then
mi = i;m = val
end
end
return m,mi
end
--]]

--[[
function maxmum(a)
local num = 1
local val = a[num]
for i,value in pairs(a) do
if value>val then
num = i
val = value
end
end
return val,num
end

print(maxmum({8,10,23,12,5}))
--]]

t = {}
s = "from=world, to=Lua"
for k, v in string.gmatch(s, "(%w+)=(%w+)") do
t[k]=v
end
for k, v in pairs(t) do
print(k,v)
end

 

print({if not package.loaded["111"] then print("nil") end}

 

 

day3

 

--面向对象

People = {} --定义一个p表

function clone(tab)
local t = {}
for key,value in pairs(tab) do
t[key] = value
end
return t
end

--[[
function People.sayhi()
print("Hello World")
end--]]

--[[People.sayhi = function()
print("Hello People ")
end--]]

function People.new(name)
local self = clone(People)
self.name = name
return self
end

People.sayhi = function(self)
print("Hello People "..self.name)
end

--[[q = clone(People)
q.sayhi()--]]

local k = People.new("丁小未")
k.sayhi(k)
k:sayhi(k)
--k.sayhi()

 

--继承

function copy(dist,tab)
for key,value in pairs(tab) do
dist[key] = value
end
end

Man = {}

Man.new = function(name)
local self = People.new(name)
copy(self,Man)
return self
end

Man.sayHello = function()
print("Man say hello")
end

Man.sayhi = function(self)
print("hi "..self.name)
end

local m= Man.new("人")
m.sayhi(m)
m:sayHello()
--m:sayhi(m)

 

 

 

lua不支持函数重载

 

--可变参数

function show(...)
local num = select('#',...)
if num>0 then
print("恩")
else
print("无")
end
end

show()

 

function clone(tab)
local t = {}
for key,value in pairs(tab) do
t[key] = value
end
return t
end

--[[
function People.sayhi()
print("Hello World")
end--]]

 

function People.new(name)
local self = clone(People)
self.name = name
return self
end

People.sayhi = function(self)
print("Hello People "..self.name)
end

 

local k = People.new("丁小未")
k.sayhi(k)

 

 

--原表

local tbA = {a = 1}
local tbB = {b = 2}
tbA.y = function(tb, k) --必须要有返回值
print("__index key:" .. k)
if k == 'a' then
return 10
end
return nil
end
--[[
local mt = {__index = tbA,
__newindex = function(t, k, v)
end
}

local mt = {__index = function(tb, k)   --这个元方法用于读取值
print("__index key:" .. k)
if k == 'a' then
return 10
end
return nil
end,
__newindex = function(tb, k, v)  --这个是用于设置值
print("__newindex key:" .. k)
end
}
]]
setmetatable(tbB, tbA)
tbB.a = 3
print(tbB.a)
--tbB.d = 3
--tbB.b = 5
--print(tbB.d)