note 74656 added to ref.network

A simple and very fast function to check against CIDR. Your previous examples are too complicated and involves a lot of functions call. Here it is (only with arithmetic operators and call only to ip2long () and split() ): <?php function ipCIDRCheck ($IP, $CIDR) { list ($net, $mask) = split ("/", $CIDR); $ip_net = ip2long ($net); $ip_mask = ~((1 << (32 - $mask)) - 1); $ip_ip = ip2long ($IP); $ip_ip_net = $ip_ip & $ip_mask; return ($ip_ip_net == $ip_net); } ?> call example: <?php echo ipCheck ("192.168.1.23", "192.168.1.0/24"); ?> ---- Server IP: 69.147.83.197 Probable Submitter: 80.97.92.73 ---- Manual Page -- http://www.php.net/manual/en/ref.network.php Edit -- https://master.php.net/note/edit/74656 Del: integrated -- https://master.php.net/note/delete/74656/integrated Del: useless -- https://master.php.net/note/delete/74656/useless Del: bad code -- https://master.php.net/note/delete/74656/bad+code Del: spam -- https://master.php.net/note/delete/74656/spam Del: non-english -- https://master.php.net/note/delete/74656/non-english Del: in docs -- https://master.php.net/note/delete/74656/in+docs Del: other reasons-- https://master.php.net/note/delete/74656 Reject -- https://master.php.net/note/reject/74656 Search -- https://master.php.net/manage/user-notes.php