Looking for a regex - 8 char min w/ 1 num and 1 char

Question

I'm looking for some help creating a regex that requires 8 char (at a minimum) along w/ 1 number and 1 char (not special char).

example: a1234567 is valid but 12345678 is not

Any help for a regex newb?

EDIT:

Thanks for the quick replies- the implementation that worked in VB is shown below

Dim ValidPassword As Boolean = Regex.IsMatch(Password, "^(?=.*[0-9])(?=.*[a-zA-Z])\w{8,}$")

Answer 1

You really need an expression with three regexes :)

 /\w{8}/

gives minimum 8 A-Z, a-z, 0-9 and _ chars

/\d/

finds a single digit

/[A-Za-z]/

finds a single letter.

So, in Perl:

$string =~ /\w{8}/ and $string =~ /\d/ and $string =~ /[A-Za-z]/

Answer 2

something like

^(?=.*[0-9])(?=.*[a-zA-Z])\w{8,}$

would work

dissected:

• ^ the beginning of the string
• (?=.*[0-9]) look ahead and make sure that there is at least 1 digit
• (?=.*[a-zA-Z]) look ahead and make sure there is at least 1 letter
• \w{8,} actually match the 8+ characters
• $ the end of the string

Edit: if you want extra characters (that don't count for the 1 letter requirement) use

^(?=.*[0-9])(?=.*[a-zA-Z]).{8,}$

this will allow for any character besides newline to be used

If you only want certain characters allowed, replace \w in the first regex with [A-Za-z0-9@#$%^&*] with your choice of symbols

^(?![0-9]$)(?![a-zA-Z]*$)\w{8,}$

Answer 3

Try this regular expression with positive look-ahead assertion:

(?=[a-zA-Z]*[0-9])(?=[0-9]*[a-zA-Z])^[0-9a-zA-Z]{8,}$

The parts are:

• (?=[a-zA-Z]*[0-9]) checks for at least one character of 0-9
• (?=[0-9]*[a-zA-Z]) checks for at least one character of the set a-z, A-Z
• ^[0-9a-zA-Z]{8,}$ checks for the length of at least 8 occurrences of 0-9, a-z, A-Z.

Or with just the basic syntax:

^([0-9][a-zA-Z][0-9a-zA-Z]{6,}|[0-9]{2}[a-zA-Z][0-9a-zA-Z]{5,}|[0-9]{3}[a-zA-Z][0-9a-zA-Z]{4,}|[0-9]{4}[a-zA-Z][0-9a-zA-Z]{3,}|[0-9]{5}[a-zA-Z][0-9a-zA-Z]{2,}|[0-9]{6}[a-zA-Z][0-9a-zA-Z]+|[0-9]{7}[a-zA-Z][0-9a-zA-Z]*|[a-zA-Z][0-9][0-9a-zA-Z]{6,}|[a-zA-Z]{2}[0-9][0-9a-zA-Z]{5,}|[a-zA-Z]{3}[0-9][0-9a-zA-Z]{4,}|[a-zA-Z]{4}[0-9][0-9a-zA-Z]{3,}|[a-zA-Z]{5}[0-9][0-9a-zA-Z]{2,}|[a-zA-Z]{6}[0-9][0-9a-zA-Z]+|[a-zA-Z]{7}[0-9][0-9a-zA-Z]*)$