$value) { header("$name: $value"); } } function isSessionStarted() { return isset($_SESSION); } function setSessionValue($name, $value) { $_SESSION[$name] = $value; } function hasSessionValue($name) { return array_key_exists($name, $_SESSION); } function getSessionValue($name) { return $_SESSION[$name]; } function deleteSessionValue($name) { unset($_SESSION[$name]); } }