Question

Before you start flaming or anything at all, READ THIS!
I have a regular expression verifying the format of a phone number entered in a form is correct.
NOW what I am hoping to find is IF someone knows a way to verify if that number exists…so if the number doesnt exist and the user enters it, user will get an error message phone number does not exist and they will be prompted to enter a WORKINg phone number….

I have looked ALL over the seas of google but could not find a phone number validator not a format checker like regex…

This is my last hope..

Answer 1

In order to check if a phone number really exists (and belongs to the user who’s filling your form), I see only one solution : try to communicate with that phone.

What’s generally done is sending an SMS with a validation code to the phone number — and ask the user to type that code once he has received the SMS.

This way, you’ll be sure that :

• The phone number exists,
• And belongs to the current user.

Of course, make sure you put some security measure in place, to prevent anyone from using your form to spam some number :

• Make sure one user cannot send more than X SMS per hour/day,
• Make sure no more than 2 or 3 SMS can be sent to the same number per day/week