Some operations of table

Declaration and Access

 local tab1 = {
    
    1, a = 2, [3] = 3}

 print(tab1[1])  -- 1
 print(tab1.a)   -- 2        a 被当作一个字符串,相当于 [a] = 2
 -- print(tab1.3)   -- 错误     3 不可这样访问
 print(tab1[3])  -- 3

table length

local tab1 = {
    
    1, 2, 3}
local tab2 = {
    
    1, a = 2, 3}
local tab3 = {
    
    1, a = 2, b = 3}

 print(#tab1) -- 3
 print(#tab2) -- 2
 print(#tab2) -- 1