Im looking for a regex that checks for:
a minimum of 2 numbers and
a minimum of 1 capital letter and
a minimum of 4 lowercase letters
And also checks for:
a maximum of 30 characters
I've been trying to make this but all my creations don't work :) You can leave the maximum out too if you can't do it, I could check it in another way.
I guess the order of those conditions is arbitrary. Therefore there is no need to do it using just 1 regexp. For each condition, you can have 1 regexp and then you can do a logical conjunction in your favorite language and it would be much more readable than one super-cool-ninja-regexp.
".*\d.*\d.*"
".*[A-Z].*"
".*[a-z].*[a-z].*[a-z].*[a-z]"
".{6,30}"
^(?=.*\d.*\d)(?=.*[A-Z])(?=.*[a-z].*[a-z].*[a-z].*[a-z]).{7,30}$ But if you want only the alphanumerics, then:
^(?=.*\d.*\d)(?=.*[A-Z])(?=.*[a-z].*[a-z].*[a-z].*[a-z])[a-zA-Z0-9]{7,30}$ (?=.*\d.*\d): at least two digits
(?=.*[A-Z]): one caps letter
(?=.*[a-z].*[a-z].*[a-z].*[a-z]): minimum four lowercase
[a-zA-Z0-9]{7,30}: length between 7-30
{7,30} to {6,30} since the 4 lowercase letters may also be 3 lowercase letters and 1 uppercase ;)
?= does? I am reading man perlre but I cannot put it together yet.(?=.*[A-Z]) means it check to see whether there is any Capital letter in front. Similar for the other (?=). It says Look-Ahead in regex.