private void btnThemPhong_Click(object sender, EventArgs e)
        {
            FormThemPhong.luaChon = "them";
            FormThemPhong form = new FormThemPhong();

            form.ShowDialog();
            if (success)
            {
                success = false;
                LoadDSPhong();
                DatLai();
            }
        }
        private void btnSuaPhong_Click(object sender, EventArgs e)
        {
            if (lblTenPhong.Text == "")
            {
                MessageBox.Show("Bạn chưa chọn phòng\nHãy chọn 1 phòng bất kỳ!", "Thông báo", MessageBoxButtons.OK, MessageBoxIcon.Warning);
                return;
            }
            FormThemPhong.idPhong = idPhong;
            FormThemPhong.luaChon = "sua";
            FormThemPhong form = new FormThemPhong();

            form.ShowDialog();
            if (success)
            {
                success = false;
                LoadDSPhong();
                DatLai();
            }
        }