Regular expression for password validation without whitespaces C#

Question

Password must contains minimum of 8 symbols.

min 2 digits in any order,

min 1 special in any order character and

must not allow whitespaces.

I have something like this:

(?=.*\d.*\d)(?=.*[$/@:?{~!^`\[\]]{1,}).{8,}

UPD solution:

(?=[^\s]*\d){2}(?=[^\s]*[$/@:?{~!^`\[\]]){1,}[^\s]{8,}

exactly 2 digits or min 2 digits? and the same for the special character — perreal, Aug 20 '14 at 09:34
refer: http://stackoverflow.com/questions/19491670/regular-expression-for-password-at-least-2-digits-and-one-special-character-and — Tim.Tang, Aug 20 '14 at 09:43
Possible duplicate of [Strong password regex](http://stackoverflow.com/questions/3131025/strong-password-regex) — ivamax9, Jan 09 '17 at 19:11

Roberto Reale · Accepted Answer · 2014-08-20T09:43:52.113

1

I would change the . into \S, if your language supports negated classes

(?=\S*\d){2}(?=\S*[$/@:?{~!^`\[\]]){1,}\S{8,}

or into [^\s], if it does not

(?=[^\s]*\d){2}(?=[^\s]*[$/@:?{~!^`\[\]]){1,}[^\s]{8,}

edited Aug 20 '14 at 09:43

answered Aug 20 '14 at 09:37

Roberto Reale

1

@Chase Since `\S{8,}` will whatever check for whitespaces, no need to use `\S` in the lookaheads. The `^` and `$` anchors are also missing. – sp00m Aug 20 '14 at 09:45

score 1 · Answer 2 · answered Aug 20 '14 at 09:41

1

Here is another one:

^(?=(?:.*\d){2})(?=.*[$/@:?{~!^`\[\]])\S{8,}$

Regular expression visualization

answered Aug 20 '14 at 09:41

sp00m

Captain · Answer 3 · 2014-08-20T09:42:23.690

0

^(?!.*\s.*)(?=.*\d.*\d)(?=.*[$/@:?{~!^`\[\]]{1,}).{8,}$

Anchoring it to the start and end, with a negative lookahead for the whitespace

edited Aug 20 '14 at 09:42

answered Aug 20 '14 at 09:36

Captain

score 0 · Answer 4 · answered Aug 20 '14 at 09:36

0

here is my suggestion:

^(?!\d+$)(?![$/@:?{~!^`\[\]]+$)[$/@:?{~!^`\[\]\d]{8,}$

NOTES： you need find another way to check at least 2 digits

answered Aug 20 '14 at 09:36

Tim.Tang

score 0 · Answer 5 · answered Aug 20 '14 at 09:38

0

 (?!.*?\s+.*?)

Just add this to your existing regex.A negative lookahead detecting one or multiple spaces.

answered Aug 20 '14 at 09:38

vks

5 Answers5