[clug-progsig] RegEx

[Shawn]

I'm working on a php migration routine where I need to take a list of 
phone numbers, which may or may not be properly entered, then format 
them into a a common format.

To do this I have found a routine 
(http://benramsey.com/archives/making-it-valid-telephone-numbers/) that 
use a regular expression to find the elements of the number.  The 
regular expression is:

$pattern = 
'/^[\(]?(\d{0,3})[\)]?[\s]?[\-]?(\d{3})[\s]?[\-]?(\d{4})[\s]?[x]?(\d*)$/';

In my case, if the number doesn't fit the usual patterns, I just return 
the original value.  (cleaning up the data while migrating, where possible)

This works well thus far, unless the number starts with the country code 
(i.e. "1-403-111-2222").  In these cases I end up with a number 
formatted as "(140) 311-1222 x.2".  So I need to modify the regex to 
handle the country code.

I've tried this:
$pattern = 
'/^(1?)[\(]?(\d{0,3})[\)]?[\s]?[\-]?(\d{3})[\s]?[\-]?(\d{4})[\s]?[x]?(\d*)$/';

(assuming I only ever see the country code of "1")  But this doesn't 
work well.

Anyone more familiar with regular expressions have any suggestions?

Thanks bunches.  I'll happily post my full format function once I get it 
working properly, should anyone need it...

Shawn