private void btnNew_Click(object sender, EventArgs e)
        {
            frmNewOrUpdateCustomer frm = new frmNewOrUpdateCustomer();

            frm.FormClosed += (s, ev) =>
            {
                frmCustomerList_Load(sender, e);
                this.WindowState = FormWindowState.Maximized;
                this.Show();
            };

            frm.ShowDialog();
        }
        private void btnEdit_Click(object sender, EventArgs e)
        {
            Customer customer = BLL.CustomerServices.GetCustomerById(Int32.Parse(dgvCustomers.CurrentRow.Cells["CustomerID"].Value.ToString()));

            frmNewOrUpdateCustomer frm = new frmNewOrUpdateCustomer(customer);

            frm.Text = "Editar cliente";

            frm.FormClosed += (s, ev) =>
            {
                frmCustomerList_Load(sender, e);
                this.WindowState = FormWindowState.Maximized;
                this.Show();
            };

            frm.ShowDialog();
        }