- preg_replace: documentation ( source)
<?php
$string = 'Site';
echo preg_replace('#.*\\\\([^\\\\]+)$#', '$1', $string) . "\n";
$string = '\Site';
echo preg_replace('#.*\\\\([^\\\\]+)$#', '$1', $string) . "\n";
$string = 'My\Special\Site';
echo preg_replace('#.*\\\\([^\\\\]+)$#', '$1', $string) . "\n";
$string = '\My\Special\Site';
echo preg_replace('#.*\\\\([^\\\\]+)$#', '$1', $string) . "\n";