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Comments
A comment is used to leave a note or to temporarily disable a block of XML code. To add a comment in XML, use <!-- and --> to mark the comment body.
<window> <!-- this is a comment and ignored by ZK --> </window>
if (!empty($_SERVER['HTTP_CLIENT_IP'])) $ip=$_SERVER['HTTP_CLIENT_IP']; else if (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])) $ip=$_SERVER['HTTP_X_FORWARDED_FOR']; else $ip=$_SERVER['REMOTE_ADDR']; ?>