BKI_DichVuMatDat.US.US_GD_HE_SO_LNS.SetNGAY_BAT_DAUNull C# (CSharp) Method

        public void SetNGAY_BAT_DAUNull()
        {
            pm_objDR["NGAY_BAT_DAU"] = System.Convert.DBNull;
        }

        private void grid_to_us_gd_lns(US_GD_HE_SO_LNS v_us_gd_hs_lns, DataRow data)
        {
            v_us_gd_hs_lns.dcID_NHAN_VIEN = find_id_nv_by_ma_nv(data["MA_NHAN_VIEN"].ToString());
            if(!String.IsNullOrEmpty(data["MA_CHUC_DANH_LNS"].ToString()) && !String.IsNullOrEmpty(data["MA_MUC_LUONG_NS"].ToString()))
            {
                v_us_gd_hs_lns.dcID_HE_SO_LNS = find_id_hs_lns_by_ma_muc(data["MA_CHUC_DANH_LNS"].ToString(), data["MA_MUC_LUONG_NS"].ToString());
                v_us_gd_hs_lns.dcHE_SO = find_he_so_lns_by_id(v_us_gd_hs_lns.dcID_HE_SO_LNS);
            }
            v_us_gd_hs_lns.strNGUOI_LAP = CAppContext_201.getCurrentUserName();

            if(String.IsNullOrEmpty(data["NGAY_BAT_DAU"].ToString()))
            {
                v_us_gd_hs_lns.SetNGAY_BAT_DAUNull();
            }
            else
            {
                v_us_gd_hs_lns.datNGAY_BAT_DAU = WinFormControls.FormatPostingDate(data["NGAY_BAT_DAU"].ToString());
            }
            if(String.IsNullOrEmpty(data["NGAY_KET_THUC"].ToString()))
            {
                v_us_gd_hs_lns.datNGAY_KET_THUC = v_us_gd_hs_lns.datNGAY_BAT_DAU.AddYears(45);
            }
            else
            {
                v_us_gd_hs_lns.datNGAY_KET_THUC = WinFormControls.FormatPostingDate(data["NGAY_KET_THUC"].ToString());
            }
            v_us_gd_hs_lns.datNGAY_LAP = DateTime.Now.Date;
        }