private void editItemToolStripMenuItem_Click(object sender, EventArgs e)
 {
     if (ItemsDataGridView.SelectedRows.Count == 1)
     {
         String ItemName   = ItemsDataGridView.SelectedRows[0].Cells["Title"].Value.ToString();
         String ItemAuthor = ItemsDataGridView.SelectedRows[0].Cells["Author"].Value.ToString();
         var    form2      = new AddBookForm();
         form2.LoadDataForEdit(ItemName, ItemAuthor);
         form2.Closed += (s, args) => this.DataFill();
         form2.ShowDialog();
     }
 }