Learning Lua programming (2) Basic Lua syntax example

Start to learn Lua programming. First, start with some simple syntax.

I. Editing Environment

We recommend a Lua programming IDE, which is very powerful. Zerobrane studio is available on Windows and Mac platforms. Click Open link official

2. Start some simple programming (see the example from http://blog.csdn.net/xiaominghimi/article/details/8770395)

For detailed syntax, refer to my previous post (reposted) blog

-- Single-line comment statement -- [[comment paragraph statement] -- references other Lua files and does not need to be added (. lua) Suffix -- require "XX" -- variables do not need to be defined, you can directly assign COUNT = 100 -- member variable local COUNT = 100 -- local variable -- method definition function Hello (...) -- print Print ("Hello Lua! "); Print (string. format (...)) end -- no separator is required for each line of code. Of course, you can also add -- access the uninitialized variable. Lua returns nil by default -- call function form Hello ("you know") -- output: -- Hello Lua! -- You know -- print the variable type isok = falseprint (type (isok) -- output: -- Boolean -- the value of the basic variable type A = Nil -- Lua is nil, which is equivalent to deleting B = 10C = 10.4d = false -- defines the string, single quotes, double quotation marks can be e = "I am" d = 'himi' -- the two strings can be connected in the following form: stringa = "hi" stringb = "mi" -- can be used ".. "symbol, connecting two strings print (stringa .. stringb) -- output: -- himi -- In addition, Lua also supports transfer characters, as shown in the following print (stringa .. "\ n ".. stringb); -- output: -- hi -- mi -- modify part of the gsub of the string in the following format: (modify the HI in the stringa string to wt) stringa = string. gsub (stringa, "Hi", "WT") print (string A); -- output: -- wt -- replace the character with the number tonumber (it will be converted automatically if it is not converted) -- replace the number with the character tostring (it will be converted automatically if it is not converted) stringc = "100" stringc = tonumber (stringc) stringc = stringc + 20 stringc = tostring (stringc) print (stringc) -- output: -- 120 -- use # print (# stringc) to get the length of a string -- output: -- 3 -- Create Table tablea = {} M = "X" tablea [m] = 100m2 = 'y' tablea [m2] = 200 print (tablea ["X"] .. "\ n ".. tablea. y) -- output: -- 100--200 -- In addition, the table can also be in the following format (starting from 1) tableb = {"4", "5", "6", "7 ", "8"} print (tableb [1]) -- output: -- 4 -- Arithmetic Operator C1 = 10 + 2C2 = 10-2c3 = 10*2c4 = 10/2 C5 = 10 ^ 2c6 = 10% 2c7 =-10 + 2 print (C1 .. "_".. c2 .. "_".. c3 .. "_".. c4 .. "_".. c5 .. "_".. c6 .. "_".. c7) -- output: -- 12_8_20_5_100_0_-8 -- control operation -- if then elseif then else endabc = 10if abc = 10 then print ("V1 ") elseif abc = 9 then print ("V2") else print ("V3") end -- output: -- V1 -- for variable = initial value, end value, step do... end -- increases from 4 (the first parameter) to 10 (the second parameter). The Unit of each increase is 2 (the third parameter). For I =, 2 do print ("for1: ".. I + 1) end --[ [Output: for1: 5for1: 7for1: 9for1: 11] -- you can leave the last parameter Unspecified. The default growth rate of 1 is for I = 4, 10 do print ("for2: ".. I + 1) end -- [Output: for2: 5for2: 6for2: 7for2: 8for2: 9for2: 10for2: 11] tablefor = {"himi1", "himi2 ", "himi3", "himi4", "himi5"} for K, V in pairs (tablefor) Do print ("for3: Key :".. k .. "value :".. v) end -- [Output: for3: Key: 1 Value: himi1for3: Key: 2 value: himi2for3: Key: 3 value: himi3for3: Key: 4 value: himi4for3: key: 5 value: himi5] -- whilew1 = 20 while tr UE do W1 = W1 + 1 If W1 = 25 then break endendprint ("while :".. w1) -- output: -- while: 25 -- repeat AA = 20 repeat AA = AA + 2 print ("Repeat :".. aa) until AA> 28 -- [Output: Repeat: 22 repeat: 24 repeat: 26 repeat: 28 repeat: 30] -- Relational operators -- do not equal to the symbol ~ = Instead! = AX = 10Bx = 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 -- output: -- GX2

-- Function description -- function funtestbackone (acount) with a returned value: Local acount = acount + 1 return acountend A = 20 print (funtestbackone ()) -- function funtestbackmore () return 2, 3end a, B = funtestbackmore () print (.. "and ".. b) -- function funtestunknow (...) with Variable Length Parameters (...) print (...) endfuntestunknow (a, B, "himi") -- closed function (one function is written in another function) function funtest1 (...) local d = 12; D = d +... function funtest2 (...) print (d) End funtest2 () end funtest1 (100) -- [[Print: 212 and 323himi112]

These are simple foundations. Let's get started with the syntax.