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<?php function get_domain($url) { if ( !preg_match("/^http/", $url) ) $url = 'http://' . $url; if ( $url[strlen($url)-1] != '/' ) $url .= '/'; $pieces = parse_url($url); $domain = isset($pieces['host']) ? $pieces['host'] : ''; if ( preg_match('/(?P<domain>[a-z0-9][a-z0-9\-]{1,63}\.[a-z\.]{2,6})$/i', $domain, $regs) ) { $res = preg_replace('/^www\./', '', $regs['domain'] ); return $res; } return false; } var_dump(get_domain("ww.mydomain.ua.com"));

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