Need Flex Regex Validation Expression for password that allows for only alphanumeric values and requires one number

Question

Hi I'm trying to setup a RegexpValidator that only accepts a string of alphanumeric characters between 6-30 characters long and requires one number. I'm new to Regular Expressions and everything I've tried seems to keep returning an invalid ValidationRsultEvent. Here's a chunk of code:

<mx:RegExpValidator id="regexValidator" source="{passwordInput}" property="text"
                        triggerEvent="" valid="onPasswordValidate(event)" invalid="onPasswordValidate(event)" />

private function validateRegister():void
{
  regexValidator.expression = "^(?=.*(\d|\W)).{6,30}$";
  regexValidator.validate();
}

Answer 1

I'm not sure what would be causing the Validation error, but as far as your regular expression goes, to match alphanumeric strings with at least one number try ^(?=.*\d)\w{6,30}$

^         # Match begining of string
(?=.*\d)  # Lookahead, assert there is any number of characters followed by a digit
\w{6,30}  # \w matches letters, digits and the underscore character, 6-30 of them
$         # Match End of string

If you want to only match letters and numbers, instead of \w you can use [0-9a-zA-Z].

Your current regular expression ^(?=.*(\d|\W)).{6,30}$ is matching any string that contains at least one character other than [a-zA-Z_] (\d|\W matches a digit, or "non-word" character), that is between 6 and 30 characters long, which does not necessarily meet the requirements you specified.

Answer 2

According to the ActionScript manual the backslash is a reserved character. Your expression should therefore look like

"^(?=.*(\\d|\\W)).{6,30}$"