learning classes not sure how to do this correctly

just starting to get used to classes, trying to figure out what i am doing wrong, i know its going to be something stupid on my part, probably really shouldn't be using a if statement or something heh just doing a basic email verification to make sure its looks like email addy so i take the post to a var PHP Code: $email_address = $_POST['email_address']; run it through this function in my class PHP Code: function check_email($address){ if (ereg('^[a-zA-Z0-9_\.\-]+@[a-zA-Z0-9\-]+.[a-zA-Z0-9\-\.]+$', $address)) return true; else return false; } and then if true i want it to continue on with the script or error out and quit back to the other page and display the error. so i have tried something like this and stuff similar but get a error Fatal error: Call to a member function on a non-object in PHP Code: if (!$keclass->check_email($email_address)) { $keclass->seterr(555); include('test.php'); exit(); } $keclass->seterr(000); include('test.php'); exit(); the seterr is just a simple thing that takes the number and puts in a session var for latter display...