function sb_core_captcha_reload_ajax_callback() { $len = isset($_POST['len']) ? $_POST['len'] : 4; $code = SB_PHP::random_string_number($len); SB_Core::set_captcha_session($code); $url = SB_Core::get_captcha_url(); $url = add_query_arg(array('code' => strtotime(SB_Core::get_current_datetime())), $url); echo $url; die; }