PHP Question

I know this is the wrong type of forum, but know there are members here that code.

Just a quick question:

I'm trying to replace or remove wildcards in keywords but think I'm over complicating it (but being crap at pattern matching so a bit stumped).


I want to remove first and last %, and if there is no % add a space.
Example replacements:
'%keyword%' => 'keyword'
'keyword%' => ' keyword'
'%keyword' => 'keyword '
'keyword' => ' keyword '


This is the way I've done it, but is there a better way of doing it:

Code:

$keyword = $keyword[0] != '%' ? ' ' . $keyword : substr($keyword, 1);
$keyword = $keyword[strlen($keyword)-1] != '%' ? $keyword . ' ' : substr_replace($keyword, '', -1);

If anyone can think of a faster way of doing it I would be grateful

preg_replace might be the better function to use.

I don't have a code sample at the moment....
PHP: preg_replace - Manual

Something like this should work:

$keyword = preg_replace('#^\%?(.*?)\%?$#', '$1', $keyword);

Thank you Oleg and Brian.

Gave it a go. It works great for removing % but doesn't add a space if there is no %.

I've changed my version to use trim() instead of substr.

Code:

$keyword = $keyword[0] != '%' ? ' ' . $keyword : ltrim($keyword, '%');
$keyword = $keyword[strlen($keyword)-1] != '%' ? $keyword . ' ' : rtrim($keyword, '%');

Performance wise, does the difference in methods matter that much?

That regular expression is quite simple, so performance wise there won't be a noticeable difference.