public static function getInstance($host = "localhost", $user = "******", $password = "", $database = "ProyectoNet")
{
if (self::$instance == null) {
self::$instance = new self();
}
if (self::$instance->dbconn == null) {
self::$instance->connectToDB($host, $user, $password, $database);
}
return self::$instance;
}
