I have a DocType/Node with a BlockList that is acting as a template. When a new page is created I want to use that Node and copy a BlockList property on it to a property on the new Node/Page.

To complicate thing the Parent BlockList has Child BlockLists.

This is what I have so far. But it doesn't copy child BlockItems that are BlockLists or change UIDs.

Can anyone help with the clone BlockList please?

public class MyContentSendingContentNotificationHandler : INotificationHandler

public MyContentSendingContentNotificationHandler(IContentService contentService, IPublishedContentQuery publishedContentQuery)
{
    _contentService = contentService;
    _publishedContentQuery = publishedContentQuery;
}

public void Handle(SendingContentNotification notification)
{
    var content = notification.Content as ContentItemDisplay;

    if (content == null)
        return;

    if (content.ContentTypeAlias == "myContent")
    {
        var settingsContent = _contentService.GetById(GetSettingsContentId());

        if (settingsContent != null)
        {
            var masterCoursePublished = _publishedContentQuery.ContentAtRoot().FirstOrDefault(x => x.ContentType.Alias == "settings")?.DescendantOfType("myContentMaster");

            if (masterCoursePublished != null)
            {
                var masterCourse = _contentService.GetById(masterCoursePublished.Id);

                if (masterCourse != null)
                {

                    foreach (var variant in notification.Content.Variants)
                    {
                        // Check if variant is a 'new variant'
                        // we only want to set the default value when the content item is first created
                        if (variant.State == ContentSavedState.NotCreated)
                        {
                            // each variant has an IEnumerable of 'Tabs' (property groupings)
                            // and each of these contain an IEnumerable of `ContentPropertyDisplay` properties
                            // find the first property with alias 'publishDate'
                            var blockList = variant.Tabs.SelectMany(f => f.Properties)
                                .FirstOrDefault(f => f.Alias.InvariantEquals("content"));
                            if (blockList is not null)
                            {
                                var masterBlockList = masterCourse.GetValue<string>("content");

                                BlockValue blockValue = JsonConvert.DeserializeObject<BlockValue>(masterBlockList);

                                // set default value of the publish date property if it exists
                                blockList.Value = masterBlockList;
                            }
                        }
                    }
                }
            }
        }
    }
}

private int GetSettingsContentId()
{
    return 1071; 
}

}