private void btnUpdateAuthors_Click(object sender, EventArgs e)
        {
            var ids           = _book.Authors.Select(a => a.Id).ToArray();
            var selectAuthors = new SelectAuthorsForm(_client, ids);

            if (selectAuthors.ShowDialog(this) == DialogResult.OK)
            {
                _book.Authors  = selectAuthors.SelectedAuthors.ToList();
                lbAuthors.Text = FormatAuthorNames(_book.Authors);
            }
        }
        private void btnUpdateAuthors_Click(object sender, EventArgs e)
        {
            var form = new SelectAuthorsForm(_client, _authorsIds.ToArray());

            if (form.ShowDialog(this) != DialogResult.OK)
            {
                return;
            }

            var authors = form.SelectedAuthors.ToArray();

            _authorsIds    = authors.Select(a => a.Id).ToList();
            lbAuthors.Text = FormatAuthorNames(authors);
        }