特定ユーザーのみに記事を閲覧させる&既読かどうかをチェックボックスで判定

<?php
if(user_logged_in()){
/*
稿useridID
*/
//ID
global $user_ID;
get_currentuserinfo();
//useridID
//ID
$arg = array(
'meta_key' => 'userid',
'meta_value' => $user_ID
);
query_posts($arg);
?>
<?php if ( have_posts() ) : while ( have_posts() ) : the_post(); ?>
<?php
//
//read1
//POSTreadread=1
if($_POST['read'] == '1' && wp_verify_nonce($_REQUEST['_wpnonce'],'nonce')){
//$post->ID
add_post_meta($post->ID,'read',1);
}
?>
<form action="./" method="post">
<!-- CSRF -->
<input type="hidden" name="_wpnonce" value="<?php echo wp_create_nonce('nonce'); ?>" />
<input type="checkbox" name="read" value="1" />
<input type="submit" value="" />
</form>
<!-- the_title()the_content() -->
<?php the_title(); ?>
<?php the_content(); ?>
<?php endwhile; else: ?>
<?php endif; ?>
<?php } else {
//
echo '';
} ?>
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