private void OnSearchAuthorsButton_Clicked(object sender, EventArgs e)
        {
            FileOutputClass.WriteArthurFileNamesToListFile(BookListPropertiesClass.PathToAuthorsNamesListFile);

            using (var win = new SearchOfBookAuthors())
            {
                win.ShowDialog();
            }
        }
        private void SelectAuthorButtonClicked(object sender, EventArgs e)
        {
            using (var win = new SearchOfBookAuthors())
            {
                win.ShowDialog();
            }

            if (string.IsNullOrEmpty(BookListPropertiesClass.AuthorsNameCurrent))
            {
                return;
            }
            this.txtAuthorName.Text = BookListPropertiesClass.AuthorsNameCurrent;
        }