# 如何在 Julia 中生成随机字母数字字符串? [英] How to generate random alphanumeric string in julia?

### 问题描述

`an = randstring(rand(Bool) ? ('A':'Z') : ('0':'9'), 12)`
b)

I am trying to generate 12 characters alphanumeric string in julia with the following snippets:
a)
`an = randstring(rand(Bool) ? ('A':'Z') : ('0':'9'), 12)`
b)

``````an = ""
for i in [1:12]
an *= randstring(rand(Bool) ? ('A':'Z') : ('0':'9'))
end
``````

but both gives either complete 12 digits or 12 alphabets but not of their combination.

please guide me in generating combination of 12 alphanumeric string.

### 推荐答案

If you don't mind using both upper and lower case letters, you can simply call `randstring(12)`:

``````julia> using Random

julia> randstring(12)
"0IPrGg0JVONT"

julia> randstring(12)
"EB5dhw4LVno7"
``````

If you want only uppercase letters (and numbers), then you need to pass `randstring` a collection that includes only uppercase letters and numbers, which you can achieve with `['A':'Z'; '0':'9']`:

``````julia> randstring(['A':'Z'; '0':'9'], 12)
"ASZQAT5YX3OL"

julia> randstring(['A':'Z'; '0':'9'], 12)
"FEV5HTGMLQ6X"
``````

Finally, note that you could provide the collection of characters as a string:

``````julia> randstring("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789", 12)
"ASZQAT5YX3OL"
``````