note 108358 deleted from reserved.variables.get by danbrown

Note Submitter: m_lajos at hotmail dot com ---- A way of removing keys from $_GET - in my opinion - in a more elegant way is by using regular expressions.

I must note, that for better performance, I only use non capturing groupings: (?:... ) 

<?php
/**
 * Remove one or more keys from the URL
 * @author Mészáros Lajos György
 * @param $key : Key( string ) or keys( array of strings ) that you want to remove
 */
function remove_key_from_url($key){
	if(is_array($key)) $key = \'(?:\'.implode(\'|\', $key).\')\';
	$url = preg_replace(\'/(?:&|(?<=\\?))\'.$key.\'(?:=[^&]*?)?(?=(?:&|$))/\', \'\', $_SERVER[\'REQUEST_URI\']);
	return preg_replace(\'/(?<=\\?)&|\\?$/\', \'\', $url);
}
?>

So let\'s assume you have the following URL:
something.php?a=12&b=134&c=foo

<?php
echo remove_key_from_url(\'c\');
// will become: something.php?a=12&b=134

echo remove_key_from_url(\'a\');
// will become: something.php?b=134&c=foo
// Note: if key is next to ?, then it will remove the following & sign, so the URL will not become something.php?&b=134&c=foo - ( that is what the 3rd line is for )

echo remove_key_from_url(Array(\'a\', \'b\', \'c\'));
// will become: something.php
// Note: the 3rd line will remove the single ? from the end

// current url here is: /foo/bar/?something&a=3
echo remove_key_from_url(\'something\');
// will become: /foo/bar/?a=3
// Note: the code can handle if no value is assigned to a key
?>

After this, you only need to pass the returned string to a header and then kill the page:

<?php
header('Location:'.remove_key_from_url('logout'));
die();
?>

I need to add, that I didn\'t do any benchmarks upon testing whether is this the faster or doing a bunch of explodes and working with arrays.
Also, I don\'t think it is possible to combine the two regexes into a single one, because the regex in the 3rd line needs to be executed after all key-value removals are done, but if possible, please give me an e-mail, I\'m really interested.

Louis from Hungary