private void OnAddAuthorsButton_Clicked(object sender, EventArgs e)
 {
     using (var win = new AdditionOfBookAuthors())
     {
         win.ShowDialog();
     }
 }
        private void OnAddNewAuthorButton_Clicked(object sender, EventArgs e)
        {
            using (var win = new AdditionOfBookAuthors())
            {
                win.ShowDialog();
            }

            this.txtAuthor.Text = BookListPropertiesClass.AuthorsNameCurrent;
            this.SetAddingNewBookControlsState();
        }
        private void OnIsNewBookAuthorCheckBox_Clicked(object sender, EventArgs e)
        {
            if (this.chkAuthor.Checked)
            {
                this.isNewAuthor = true;
                return;
            }

            using (var win = new AdditionOfBookAuthors())
            {
                win.ShowDialog();
            }

            this.isNewAuthor = false;
        }