regex error preg_replace_callback() : Unknown modifier '.' in [duplicate]

Question

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Warning: preg_replace(): Unknown modifier (3 answers)

Closed 2 years ago.

I got the following string:

last_name, first_name
bjorge, philip
kardashian, [kghim]
mer#$##Code:menu:51587daa7030e##$#cury some more
data #$##Code:menu:515r4387daa7dsf030e##$#, freddie

im trying to replace the Codes in the middle with the function: 'codeParser' the regex is:

$PC_File = preg_replace_callback("(?=\#\$\#\#).*?(?<=\#\#\$\#)", 'codeParser', $PC_File);

but getting this error:

PHP Warning:  preg_replace_callback() : Unknown modifier '.'

Answer 1

You need to wrap your regular expression in delimiters. It's considering () to be the delimiters right now, and the . as a modifier (which is of course invalid).

"/(?=#\\$##).*?(?<=##\\$#)/"

(I'm also pretty sure the # do not need to be escaped unless you were using them as delimiters)

EDIT: You need \\ to properly escape the $ in double-quotes.