Regex password validation combination

Question

Need some help with a Regex please, I have accomplished what I need to do but only with a two step process, I have tried multiple rethinks but am unable to make the two regex's into only one. Could someone please point me in the right direction? (have been through lots of tutorials, builders and what not but do not seem clever enough to figure it out!)

This is for password validation, ensuring at least one char, one number, one uppercase letter and ensuring first and last chars are not digits and password is at least 8 chars long. This is the server side version but I will also be placing the regex on client side too.

private bool ValidatePassword(string input)
{
    bool _return;
    var regEx = new Regex(@"^(?=(.*\d))(?=.*[a-z])(?=.*[A-Z])(?!\d).{8,}$");
    _return = regEx.IsMatch(input);

    if (_return)
    {
        regEx = new Regex(@"[^1](\D*)$");
        _return = regEx.IsMatch(input);
    }

    return _return;
}

Would be helpful if you could tell us *what* the problem is with your current code. — tnw, Mar 10 '14 at 14:24
Search for "regex password strength", not "validation": http://stackoverflow.com/questions/5142103/regex-for-password-strength — Alexander, Mar 10 '14 at 14:28
So your second regex is just to check the last character isn't a digit? In that case, just change the end of the first regex to: `.{7,}\D$` — Matt Burland, Mar 10 '14 at 14:29
@Alexander: Helpful, but doesn't really answer the OP's question. — Matt Burland, Mar 10 '14 at 14:30
@Matt It's exactly what he wants. Run several "checks" against a string with a single regex. — Rawling, Mar 10 '14 at 14:33
@Rawling: No it isn't. It doesn't include the first and last non-digit restriction that the OP is having trouble with. — Matt Burland, Mar 10 '14 at 14:43

score 0 · Accepted Answer · answered Mar 10 '14 at 14:31

0

Would this work?

var regEx = new Regex(@"^(?=(.*\d))(?=.*[a-z])(?=.*[A-Z])(?!\d).{7,}\D$");

Demo here: http://rubular.com/r/xyiSz3RCQr

answered Mar 10 '14 at 14:31

Matt Burland

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This is perfect - thank you Mark, been going round in circles for a couple of hours and you sort my head out in minutes! – T1gg3rB0unC3 Mar 10 '14 at 14:38

score 0 · Answer 2 · answered Mar 10 '14 at 14:36

0

Try this:

^\D{1}((?=(.*\d))(?=.*[a-z])(?=.*[A-Z])(?!\d).{6,})\D{1}$

answered Mar 10 '14 at 14:36

amiry jd

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Regex password validation combination

2 Answers2