Warning: preg_replace(): Unknown modifier '['

Question

Say I'm making a simple BBCode function using regex, and I want the [color=] tag to stop parsing at the first semicolon to avoid exploits. Now I've seen this question all over stackoverflow, but it never shows how to implement it.

$regex = '/\[colour\=/[^;]*/](.*?)\[\/colour\]/is';
$replace = '<span style="color: $1">$2</span>';

Why is this giving me the error in the title? I can't figure out regex for the life of me, so I'm really stuck here.

If it helps any, here is the original regex I wanted to implement:

/[^;]*/

You should always validate your regular expression first, e.g. on https://regex101.com/#pcre — Tomasz Racia, Jan 08 '15 at 14:13

Toto · Answer 1 · 2015-01-08T15:10:07.160

3

Escape the slash:

$regex = '/\[colour\=\/[^;]*\/](.*?)\[\/colour\]/is';
//            here __^    __^

or use another delimiter:

$regex = '#\[colour=/[^;]*/](.*?)\[/colour\]#is';

But I guess the regex is:

$regex = '#\[colour=/[^;]*\](.*?)\[/colour\]#is';
//       backslash here __^

According to the replacement part:

$regex = '#\[colour=([^;]+)\](.*?)\[/colour\]#is';
$replace = '<span style="color: $1">$2</span>';

Edit according to comment:

$regex = '#\[colour=(.*?)\](.*?)\[/colour\]#is';
$replace = '<span style="color: $1">$2</span>';

edited Jan 08 '15 at 15:10

answered Jan 08 '15 at 14:10

Toto

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None of them seem to work. They all just make the [colour] tag not parse (change into html tags) at all. – sezgtfsdfsd Jan 08 '15 at 14:15
"none seem to work" - then the regex isn't matching anything. So start debugging to find out why. – Marc B Jan 08 '15 at 14:21
I'm sorry but I don't know what you mean by example. The code in my OP is already what I've got. – sezgtfsdfsd Jan 08 '15 at 14:22
That just seemed to create this: ` [colour=red;font-size:50pt]test with semicolon` – sezgtfsdfsd Jan 08 '15 at 14:31
`echo parseBBCode('[colour=blue]normal test[/colour] [colour=red;font-size:50pt]test with semicolon[/colour]');` where the parseBBCode function is pretty much what I showed in the OP (but with a preg_replace return) – sezgtfsdfsd Jan 08 '15 at 14:38
@sezgtfsdfsd: See my edit, is that what you want? – Toto Jan 08 '15 at 15:10
That was where I was at the beginning. I want it to only parse up to the first semicolon, not including the semicolon itself. – sezgtfsdfsd Jan 11 '15 at 16:15

score 0 · Answer 2 · answered Jan 08 '15 at 14:23

0

Try this snippet of the code:

$text = '[colour=red]Text in red[/colour]';
$regex = '/\[colour=([^;]*)\](.*?)\[\/colour\]/is';
$replace = '<span style="color: $1">$2</span>';

echo preg_replace($regex, $replace, $text);

answered Jan 08 '15 at 14:23

Tomasz Racia

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Warning: preg_replace(): Unknown modifier '['

2 Answers2