private void btnMatDoSuDung_ThongKe_Click(object sender, EventArgs e) { if (cbMatDoSuDung_Thang.Text != "") { List <PhongDTO> dsphg = new List <PhongDTO>(); dsphg = PhongBUS.LayDSPhong(); int[] arrNgayThue = new int[dsphg.Count]; arrNgayThue = PhongBUS.LapBaoCaoMatDo(Int32.Parse(cbMatDoSuDung_Thang.Text)); int tong = 0; for (int i = 0; i < dsphg.Count; i++) { tong += arrNgayThue[i]; } dgv_MatDoSudung.Rows.Clear(); for (int i = 0; i < dsphg.Count; i++) { dgv_MatDoSudung.Rows.Add(i + 1, dsphg[i].MaPhong, arrNgayThue[i], (Convert.ToDouble(arrNgayThue[i]) * 100 / Convert.ToDouble(tong)).ToString("00.00") + "%"); } } else { MessageBox.Show("Bạn chưa chọn tháng", "Lỗi", MessageBoxButtons.OK, MessageBoxIcon.Error); } }