/**
* Returns true if the give $userAgent is from a robot
* @param string $userAgent
* @return bool
*/
public static function isRobot($userAgent)
{
if (self::$_is_robot !== null) {
return self::$_is_robot;
}
self::$_is_robot = false;
$userAgent = strtolower($userAgent);
foreach (self::$robots as $key) {
if (strpos($userAgent, $key) !== false) {
self::$_is_robot = true;
break;
}
}
return self::$_is_robot;
}