note 96890 added to filter.filters.validate

Take caution when using the FILTER_VALIDATE_BOOLEAN filter as it seems to have different behaviors when used in the filter_var() vs. the filter_input() functions. To demonstrate, let's parse some arguments from a GET request (notice how arg2 is NOT set): example.com/script.php?arg1=yes&arg3=no <?php // filtering by variable $var1 = filter_var($_GET["arg1"], FILTER_VALIDATE_BOOLEAN); $var2 = filter_var($_GET["arg2"], FILTER_VALIDATE_BOOLEAN); $var3 = filter_var($_GET["arg3"], FILTER_VALIDATE_BOOLEAN); // filtering by input $input1 = filter_input(INPUT_GET, "arg1", FILTER_VALIDATE_BOOLEAN); $input2 = filter_input(INPUT_GET, "arg2", FILTER_VALIDATE_BOOLEAN); $input3 = filter_input(INPUT_GET, "arg3", FILTER_VALIDATE_BOOLEAN); // as expected... var_dump($var1); // bool(true) var_dump($var2); // bool(false) var_dump($var3); // bool(false) // NULL is not an expected return... var_dump($input1); // bool(true) var_dump($input2); // NULL var_dump($input3); // bool(false) ?> As per the documentation, the return is limited to true XOR false unless the FILTER_NULL_ON_FAILURE flag is set, but it seems as if this flag is set automatically with the filter_input() function. (Note: same behavior for filter_var_array() vs. filter_input_array()) ---- Server IP: 69.147.83.197 Probable Submitter: 80.174.182.168 ---- Manual Page -- http://www.php.net/manual/en/filter.filters.validate.php Edit -- https://master.php.net/note/edit/96890 Del: integrated -- https://master.php.net/note/delete/96890/integrated Del: useless -- https://master.php.net/note/delete/96890/useless Del: bad code -- https://master.php.net/note/delete/96890/bad+code Del: spam -- https://master.php.net/note/delete/96890/spam Del: non-english -- https://master.php.net/note/delete/96890/non-english Del: in docs -- https://master.php.net/note/delete/96890/in+docs Del: other reasons-- https://master.php.net/note/delete/96890 Reject -- https://master.php.net/note/reject/96890 Search -- https://master.php.net/manage/user-notes.php