private void addButton_Click(object sender, EventArgs e) { if (_itemManager.isNameExist(itemNameTextBox.Text)) { MessageBox.Show(itemNameTextBox.Text + " Already exist!!!"); return; } if (String.IsNullOrEmpty(itemPriceTextBox.Text)) { MessageBox.Show(" Price must be Added !!!"); return; } bool isAdded = _itemManager.AddData(itemNameTextBox.Text, Convert.ToDouble(itemPriceTextBox.Text)); if (isAdded) { MessageBox.Show(" Saved."); } else { MessageBox.Show(" Not Saved !!!."); } showDataGridView.DataSource = _itemManager.ShowData(); }