Undefined Index - is this how you "declare" get & post?

Hi List, Since I started using error_reporting(E_ALL), I havent found (in my opinion) a good way to declare GET and POST variables when getting them from a form or querystring. I have searched google and the docs for several hours now without much luck. <?php error_reporting(E_ALL); // This line stops the error reporting, else I get - Notice: Undefined index: i in..... $HTTP_GET_VARS["i"]=""; if ($HTTP_GET_VARS["i"] == "") { include("myfile.php"); } ?> Is there a better way? I have tried var $i (only for classes I've discovered) settype($i, "integer") Thanks in advance.