Warning: preg_match_all(): Unknown modifier '4'

Question

I have the following error:

Warning: preg_match_all(): Unknown modifier '4' in file.php on line 410

Code on line 410:

preg_match_all("#$replacement_pattern#is", $text, $arr);

Can someone please help me to fix this problem?

Can you provide enough code to recreate the problem, ie include your $pattern with sample $text, and $array — Ryan Tuosto, Jul 06 '17 at 23:15
Use `preg_match_all("#" . preg_quote($replacement_pattern, "#") . "#is", $text, $arr);` — Wiktor Stribiżew, Jul 06 '17 at 23:18
I think, that problem is here $replacement_pattern = preg_replace('#\{[A-Z0-9_]+\}#', '(.+?)', $replacement_pattern); but I can't fix it. — dawidex44, Jul 06 '17 at 23:35
Try `$replacement_pattern = str_replace('#', '\\#', trim($row['bbcode_in'])`);` (Line 396) — Wiktor Stribiżew, Jul 07 '17 at 09:39

score 0 · Answer 1 · answered Jul 09 '17 at 21:21

The issue is caused by the pattern having an unescaped regex delimiter that is # in your case.

At line 396, the $row['bbcode_in'] is a simple string, and all # symbols can be escaped then, so that afterwards you could use # as regex delimiters.

So, Line 396 must look like:

$replacement_pattern = str_replace('#', '\\#', trim($row['bbcode_in']));

Warning: preg_match_all(): Unknown modifier '4'

1 Answers1