From: "Jesús Gabriel y Galán" <jgabrielygalan@...>
Date: 2010-02-12T03:28:08+09:00
Subject: Re: n00b: text processing from magnetic stip input

On Thu, Feb 11, 2010 at 7:12 PM, John Gesimondo <john@jmondo.com> wrote:
> Hello everyone!
>
> I'm trying to make a program and I'm really bad at text processing. The
> input is a magnetic stripe of a card (coming straight off a card
> reader). I'm trying to split the output so that each part can get stored
> in a variable.
>
> Here's what comes off the card:
> %B6007503004905860^GEVIMSEDO/JRPN
> P^894212333300?;604750230190488515=993612044400050600?+E?
>
> And here's what I want (with relevant details):
>
> iso = 6007503004905860 [always the same length]
>
> last_name = Gevimsedo [variable length, always following carrot symbol]
>
> first_name = Jrpn [variable length, always after slash]
>
> middle_name = P [ either one letter, or non-existent after frist name
> separated by a space]
>
>
> If anyone could make that happen, you'd make my day/week/etc. I've been
> trying for a while, but I'm clearly too much of a n00b.

Show us what you tried, it's easier to help that way. Anyway, you
could build a regular expression that matches the fixed parts of the
string while capturing in groups your "variables". To get you started:

regex = %r{\%B(.*)\^(.*)/ [...and so on...] }

then match the string against that regex using:

http://ruby-doc.org/core/classes/String.html#M000778

For example:

match = yourstring.match(regex)
puts match.captures

Hope this helps,

Jesus.