Re: regex for multiple line breakes
| From: | Fernando Castillo Aparicio | Date: | Wed, 14 Oct 2009 11:01:54 +0000 |
| Subject: | Re: regex for multiple line breakes | ||
| References: | 1 2 3 4 | Groups: | php.general |
| Request: | Send a blank email to php-general+get-298893@lists.php.net to get a copy of this message | ||
Right. I saw it later. To be completely multiplatform I'd use a grouping: (\n|\r|\r\n){2,}. If
I'm not wrong, these are all the actual formats for a new line.
If we replace \r with a newline we could fail if the text comes from a MAC OS.
________________________________
De: Ashley Sheridan <ash@ashleysheridan.co.uk>
Para: Merlin Morgenstern <merlin_x@fastmail.fm>
CC: php-general@lists.php.net
Enviado: mié,14 octubre, 2009 12:44
Asunto: Re: [PHP] regex for multiple line breakes
On Wed, 2009-10-14 at 12:42 +0200, Merlin Morgenstern wrote:
> That sounds very logical but does not work unfortunatelly.
> The result is the same. It removes all linebreakes but one.
> I would like to pass this one:
>
> ---------
> first line
>
> second
> third
> ---------
>
> But not this one:
> ---------
> third
>
>
>
>
> forth
> --------
>
>
>
> Fernando Castillo Aparicio schrieb:
> > You are replacing 1 or more matchs of a new line. To match 2 or more you can use
> > "{2,}". It's a range, first number means min matches, second max matches. Omitting
> > last number means no max limit.
> >
> > $data[txt] =
> > preg_replace('
[\r\n]{2,}',"\n",$data[txt]);
> >
> >
> >
> > ________________________________
> > De: Merlin Morgenstern <merlin_x@fastmail.fm>
> > Para: php-general@lists.php.net
> > Enviado: mié,14 octubre, 2009 12:17
> > Asunto: [PHP] regex for multiple line breakes
> >
> > Hi there,
> >
> > I am trying to remove multiple linebreakes from a textarea input. Spammers tend to insert
> > multiple line breakes. The problem is, that I want to allow 2 line breaks so basic formating should
> > be allowed.
> >
> > I am doing this by regex:
> > $data[txt] =
> > preg_replace('[\r\n]+',"\n",$data[txt]);
> >
> > I would need a regex that allows \r\n\r\n, but not more than this.
> >
> > Thank you for any help,
> >
> > Merlin
> >
> > -- PHP General Mailing List (http://www.php.net/)
> > To unsubscribe, visit: http://www.php.net/unsub.php
> >
> >
> >
>
You still have an issue with your regex:
$data[txt] = preg_replace('[\r\n]+',"\n",$data[txt]);
Even if you replace the + with a {2,} you are asking it to match any one
of the characters in the square brackets twice or more and replace it
with a single \n. If your line breaks actually do consist of the \r\n
pattern, then the {2,} will match those two characters, not two sets of
those characters. You might be better off replacing all \r characters
with an empty string, and then matching against the \n character only.
Thanks,
Ash
http://www.ashleysheridan.co.uk