//An action handler that add inventories to that inventories
        private void btnAddInventory_Click(object sender, EventArgs e)
        {
            inventories.AddInventories(txtBookTitle.Text, txtAuthor.Text, txtPublisher.Text);

            List <InventoryItems> items = inventories.getListsItems();

            if (lstSummary.Items.Count > 0)
            {
                lstSummary.Items.Clear();
            }
            foreach (InventoryItems item in items)
            {
                lstSummary.Items.Add("Item successfully Added to Inventory");
                lstSummary.Items.Add("");
                lstSummary.Items.Add(label2.Text + " " + item.getbookTitle());
                lstSummary.Items.Add(label3.Text + " " + item.GetAuthorName());
                lstSummary.Items.Add(label4.Text + " " + item.getPubisher());
                lstSummary.Items.Add("");
                lstSummary.Items.Add("*****************************");
            }
            clearControls();
        }