unknown modifier error in my preg_replace attempt

Question

so I did

$subject = 'sakdlfjsalfdjslfad <a href="something/8230">lol is that true?</a> lalalala';

$subject = preg_replace('<a href="something\/([0-9]+)">(.+?)<\/a>', '$1', $subject);

echo $subject;

whereby the objective is to have $subject return

'sakdlfjsalfdjslfad lol is that true? lalalala'

but then PHP returned

warning: preg_replace(): Unknown modifier '('

what did I do wrong?

dldnh · Accepted Answer · 2012-03-26T14:50:42.683

1

the pattern needs delimiters -- slashes, e.g.

'/<a href="something\/([0-9]+)">(.+?)<\/a>/'

edited Mar 26 '12 at 14:50

answered Mar 26 '12 at 14:45

dldnh

8,923
3
40
52

score 1 · Answer 2 · answered Mar 26 '12 at 14:48

1

You need delimiters around the pattern:

$subject = preg_replace('#<a href="something/([0-9]+)">(.+?)</a>#', '$1', $subject);

answered Mar 26 '12 at 14:48

Toto

89,455
62
89
125

score 0 · Answer 3 · answered Mar 26 '12 at 14:51

A PCRE (Perl Compatible Regular Expression) should be surrounded by delimiters, so

<a href="something\/([0-9]+)">(.+?)<\/a>

should be

/<a href="something\/([0-9]+)">(.+?)<\/a>/

I have used slashes (/) - but there are lots of choices

When using the PCRE functions, it is required that the pattern is enclosed by delimiters. A delimiter can be any non-alphanumeric, non-backslash, non-whitespace character.

Often used delimiters are forward slashes (/), hash signs (#) and tildes (~). The following are all examples of valid delimited patterns.

here are the docs for delimiters in pregex

unknown modifier error in my preg_replace attempt

3 Answers3