private void btn4_delete_Click(object sender, EventArgs e)
        {
            try
            {
                //Choice to cancel or accept item deletion
                DialogResult choice = MessageBox.Show("Are you sure you would like to delete this item?", " ", MessageBoxButtons.YesNo);
                switch (choice)
                {
                    case DialogResult.Yes:
                        int delete;
                        delete = dataGridView_inventory.CurrentCell.RowIndex;
                        Product item = IM.getItemList()[delete];
                        IM.removeItem(item);
                        dataGridView_inventory.DataSource = IM.getItemList();
                        break;
                    case DialogResult.No:
                        break;
                }

            }
            catch(Exception ex)
            {
                MessageBox.Show("Please make sure that you've selected an item to delete.");
            }
        }