Formatting (input masking) phone numbers in ZoHo Creator

Formatting (input masking) phone numbers in ZoHo Creator

I've been searching most of the day for this answer;  how do you format the 'field' in a form that displays a ten (10) digit phone number correctly (as is displayed in most web-based forms).  I can easily do this using Microsoft Access, however, I don't know how to do this in ZoHo Creator.
 
(123) 456 - 7890
 
The idea is to just type in all of the numbers and "after updating" the format will be assembled to look like the above example.
 
I keep reading about using 'strings', but since I do not know how to build and/or implement one of these strings (using ZoHo Creator) I need a script, and directions of how and where to put this script.
 
I'm building an application using ZoHo Creator, and there are several fields that will contain phone numbers (Work, FAX, Work Cell, Home, Personal Cell, etc.)
 
Thanks in advance.
 
Al