public ContentPageTree(Guid?parent, IPageContentProvider provider)
        {
            this.provider = provider;
            var content = parent != null?provider.GetPage(parent.Value) : new ContentPage()
            {
                Id = Guid.Empty, Name = "Домашняя страница"
            };

            this.Root = new ContentPageTreeItem(content, null);
            this.GerenateForParent(this.Root);
        }
 public PaginationItemProvider(IPageContentProvider pageContentProvider)
 {
     _pageContentProvider = pageContentProvider ?? throw new ArgumentNullException(nameof(pageContentProvider));
 }