note 118247 deleted from function.array-key-exists by crell

Note Submitter: Venkata Subbaraju ---- array_key_exists perfect for $_GET . As there will be browser level restriction on length of URL , number of keys in $_GET global variable will be very limited . So array_key_exists will not cause any performance overhead in this context . isset function can be conveniently ignored while handling $_GET variable. But for $_POST , the max array size has to be configure in server PHP configuration . So cannot rely on array_key_exists for $_POST if max array size is not optimized . Here is an example with array_key_exists switching between content-types : if(array_key_exists('format',$_GET)) { if($_GET['format']=="json") { header('Content-Type: application/json'); } else{ //handle any other format whitelisted for the application } } else { error_log("format parameter missing . using default html format"); header('Content-Type: text/html'); }