I agree about the "pet peeve". Often, I try to register on a US site and it won't accept my
UK phone number.
in reply to Re: Re: Re: Another LostS Question - Phone Number Checks
in thread Another LostS Question - Phone Number Checks
Even UK systems screw up since we often have number changes and
the websites often don't change quickly enough.
Suggestion (adding to comments by [id://kjherron]) :
Allow any format, strip down to digits, and check for a reasonable
number of digits to allow for international dialing codes, etc.
then leave it at that.
If you want real validation, you'll need to check the dialing codes for each potential
country to see if they are OK, and KEEP THE DATABASE UP-TO-DATE.