if ($class !~ /^[a-z0-9_]*$/i) {
        print $cgi->header();
        print "<h1> You tried something that's not allowed! </h1><br><br>";
        exit();
}


##</code><code>##

        eval {
                require $class . ".pm";
        };
        if ($@) {
                print $cgi->header();
                print "$@";
                print "<h1> The class '$class' does not exist! </h1><br><br>";
        } else {
                # Do your stuff.
                $class->main($cgi,$user);
        }