包含括号的PHP preg_replace值

Question

In my PHP script, I want to use preg_replace to replace values, skipping any value that is within the HTML tags <a> and </a>. The values are contained within arrays, so the following is a snippet of the current code that is run within a loop:

$Used[$i] = preg_replace("~<a[^>]*>.*?</a\s*>(*SKIP)(*FAIL)|{$MatchFinal[$i]}~","{$MatchLinkFinal[$i]}", $value);

The code works, except for values that contain parentheses ( or ).

For example, if $MatchFinal[$i] contains the value Fatigue, then it replaces it with a value $MatchLinkFinal[$i] that includes a link: <a>...Fatigue...<a>. However, if $MatchFinal[$i] contains the value Hair (Dry), then it does not replace it.

Why are values that contain parentheses not being replaced?

Note: Values that contain spaces and/or apostrophes are being replaced.

I tried escaping the parentheses...

$MatchFinal[$i] = str_replace("(", "\(", $MatchFinal[$i]);

and

$MatchFinal[$i] = str_replace(")", "\)", $MatchFinal[$i]);

...but I received an error message:

Warning: preg_replace(): Compilation failed: missing ) at offset 51

Answer 1

You want preg_quote()

$MatchFinal[$i] = preg_quote($MatchFinal[$i]);