I am not really good at regular expression and I was trying to come up with a regular expression that could validate the isbn numbers in my php code,
I will strip the dashes and spaces from the string so I will make sure that the string has only the digits plus that optional x or X. I was wondering if one you regular expression gurus out there could help me figure this out.
Thank you,
^ISBN\s(?=[-0-9xX ]{13}$)(?:[0-9]+[- ]){3}[0-9]*[xX0-9]$