我的帖子类型“ebrd\\U视频”上有一个元框，它使用复选框将视频设置为“特色视频”。

我想将状态为“featured=on”的视频数量限制为1个。因此，当我将视频设置为特色视频并发布/更新该视频时，所有其他视频都设置为“特色=关闭”。

如果有帮助，下面是创建元框的代码：

// Add the Top and Featured News Meta Boxes ----------------------------------------//

add_action( \'add_meta_boxes\', \'ebrd_add_post_metaboxes\' );

function ebrd_add_post_metaboxes() {
    add_meta_box(\'ebrd_feat\', \'Post status\', \'ebrd_feat\', \'ebrd_videos\', \'side\', \'default\');
}

// Featured Metabox

function ebrd_feat(){
    global $post;
    $custom = get_post_custom($post->ID);
    if(isset($custom["ebrd_home_feat"][0])) $ebrd_home_feat = $custom["ebrd_home_feat"][0];
    else $ebrd_home_feat = \'off\';

    // We\'ll use this nonce field later on when saving.  
    wp_nonce_field( \'my_meta_box_nonce\', \'meta_box_nonce\' ); 
?>

<input type="checkbox" name="ebrd_home_feat" <?php if( $ebrd_home_feat != \'off\' ) { ?>checked="checked"<?php } ?> />  Home feature?
<?php
} 

add_action(\'save_post\', \'save_details\');

function save_details($post_ID = 0) {
    $post_ID = (int) $post_ID;
    $post_type = get_post_type( $post_ID );
    $post_status = get_post_status( $post_ID );

    // if our nonce isn\'t there, or we can\'t verify it, bail 
    if( !isset( $_POST[\'meta_box_nonce\'] ) || !wp_verify_nonce( $_POST[\'meta_box_nonce\'], \'my_meta_box_nonce\' ) ) return;

    // if our current user can\'t edit this post, bail  
    if( !current_user_can( \'edit_post\' ) ) return; 

    if(isset($_POST["ebrd_home_feat"])) $ebrd_home_feat = $_POST["ebrd_home_feat"];
    else $ebrd_home_feat = \'off\';

    if ($post_type) {
        update_post_meta($post_ID, "ebrd_home_feat", $ebrd_home_feat);
    }
   return $post_ID;
}