Password validation with regular expression

Question

I'm trying to use a regular expression to validate a password. I've tried a number of different regex's that seem to work elsewhere but do not work in HTML DB. This includes a couple that I wrote and that I found on regex web sites. Specifically, I'm trying to validate that a string has:
1. at least one special character
2. at least one numeric character
3. no more than 6 consecutive characters
4. has a length between 8 and 14
Does anyone know why some regular expressions do not work in HTML DB that work elsewhere or has anyone done a regex similar to this in HTML DB.
Thanks!
- Brian

Answer 1

I see, I will use the [0-9] instead. The expression still does not work though. I simplified the expression down to try and figure out what doesn't work and it seems like it's the "?=".
1. I first entered the expression:
([:alnum:]*[0-9])
This expression just says there must be a number and it works fine in HTML DB.
2. I extended it to:
([:alnum:]*[0-9])([:alnum:]*[a-z])
This expression says that there must be a number followed by a letter. In this example "1a" works but "a1" does not.
3. To make it not care about the order I would normally add "?=" like so:
(?=[:alnum:]*[0-9])(?=[:alnum:]*[a-z])
This should work for "a1" or "1a" because the ? says the order doesn't matter. When I try this in HTML DB neither "1a" or "a1" work.
Any ideas?
Thanks
- Brian