Got it, thank you Todd.
I usually tend to use string based functions instead of regex, but sometimes
regex is a better option.
On Sat, Mar 7, 2009 at 12:16 AM, haliphax <haliphax@xxxxxxxxx> wrote:
> On Fri, Mar 6, 2009 at 4:01 PM, Nitsan Bin-Nun <nitsan@xxxxxxxxxxxx>
> wrote:
> > On Fri, Mar 6, 2009 at 11:53 PM, haliphax <haliphax@xxxxxxxxx> wrote:
> >>
> >> On Fri, Mar 6, 2009 at 3:44 PM, Nitsan Bin-Nun <nitsan@xxxxxxxxxxxx>
> >> wrote:
> >> > I'm not looking for other ideas, the main thing here is that I have
> >> > about
> >> > 30-100 regex's in the database and the script fetches them and applies
> >> > them
> >> > to the string. I can't build again the engine and I'm not going to do
> >> > that.
> >> > I'm trying to solve my problem ;) If you have any ideas regarding my
> >> > issue
> >> > and not going in another way this would be very appreciated.
> >>
> >> Nitsan,
> >>
> >> I think it's because you're referencing the capture group with index
> >> instead of index 2. Also, I don't understand why you have the pipe
> >> ("|") character in your regex string... is that part of your engine?
> >>
> >> This code:
> >>
> >> $orig = 'http://www.zshare.net/video/541070871c7a8d9c';
> >> $matches = array();
> >> preg_match('#http://(www\.)zshare\.net/video/([^/]+)#', $orig,
> $matches);
> >> echo $matches[2];
> >>
> >> Grabs the correct match:
> >>
> >> 541070871c7a8d9c
> >>
> >> The regex pattern works with the pipe char, but it is unnecessary and
> >> may lead to some strange behavior.
> >
> > Thank you Todd, I also want to capture when I don't have the www in the
> > beginning of the URL.
> > For instance, try to execute your code with
> > $orig = 'http://zshare.net/video/541070871c7a8d9c';
> >
> > That's why I used (www\.|), but I'm not a regex expert and I'm sure there
> a
> > way better solutions to this problem.
>
> http://www.regular-expressions.info is your best friend. Spend an
> afternoon playing around on it... that's really the only advantage I
> have over someone who hasn't.
>
> Anyway, you can make that entire group optional with the ? character like
> so:
>
> #http://(www\.)?zshare\.net/video/([^/]+)#
>
> And if you don't want it to be captured, making the URL suffix index 1
> instead of index 2, do this:
>
> #http://(?:www\.)?zshare\.net/video/([^/]+)#
>
> Any group that begins with "?:" will not be captured in a match index. To
> recap:
>
> $pattern = '#http://(?:www\.)?zshare\.net/video/([^/]+)#';
> $orig = 'http://zshare.net/video/541070871c7a8d9c';
> $matches = array();
> preg_match($pattern, $orig, $matches);
> echo $matches[1] . "\n";
> $orig = 'http://www.zshare.net/video/541070871c7a8d9c';
> preg_match($pattern, $orig, $matches);
> echo $matches[1] . "\n";
>
> Produces this output:
>
> 541070871c7a8d9c
> 541070871c7a8d9c
>
> Hope this helps,
>
>
> --
> // Todd
>
