将null作为SQLParameter DateTime值传递

Question

我有以下查询:

INSERT INTO CWS_FORWARDING_PROFILE
           (TNR_COMPANY_PROFILE,BOL_FORWARD_MAIL,BOL_FORWARD_SMS,BOL_FORWARD_MESSAGES
           ,DT_MO_FROM1,DT_MO_FROM2,DT_MO_FROM3,DT_MO_TO1,DT_MO_TO2,DT_MO_TO3
           ,DT_TU_FROM1,DT_TU_FROM2,DT_TU_FROM3,DT_TU_TO1,DT_TU_TO2,DT_TU_TO3
           ,DT_WE_FROM1,DT_WE_FROM2,DT_WE_FROM3,DT_WE_TO1,DT_WE_TO2,DT_WE_TO3
           ,DT_TH_FROM1,DT_TH_FROM2,DT_TH_FROM3,DT_TH_TO1,DT_TH_TO2,DT_TH_TO3
           ,DT_FR_FROM1,DT_FR_FROM2,DT_FR_FROM3,DT_FR_TO1,DT_FR_TO2,DT_FR_TO3
           ,DT_SA_FROM1,DT_SA_FROM2,DT_SA_FROM3,DT_SA_TO1,DT_SA_TO2,DT_SA_TO3
           ,DT_SU_FROM1,DT_SU_FROM2,DT_SU_FROM3,DT_SU_TO1,DT_SU_TO2,DT_SU_TO3)

            VALUES(@tnrProfile, @forwardMail, @forwardSms, @forwardMessages,
                    @MoFrom1, @MoFrom2, @MoFrom3, @MoTo1, @MoTo2, @MoTo3,
                    @TuFrom1, @TuFrom2, @TuFrom3, @TuTo1, @TuTo2, @TuTo3,
                    @WeFrom1, @WeFrom2, @WeFrom3, @WeTo1, @WeTo2, @WeTo3,
                    @ThFrom1, @ThFrom2, @ThFrom3, @ThTo1, @ThTo2, @ThTo3,
                    @FrFrom1, @FrFrom2, @FrFrom3, @FrTo1, @FrTo2, @FrTo3,
                    @SaFrom1, @SaFrom2, @SaFrom3, @SaTo1, @SaTo2, @SaTo3,
                    @SuFrom1, @SuFrom2, @SuFrom3, @SuTo1, @SuTo2, @SuTo3);

我添加我的DateTime参数如下:

SqlParameter moFrom1Param = new SqlParameter("@MoFrom1", dTOForwarding.MoFrom1);
            moFrom1Param.IsNullable = true;
            moFrom1Param.Direction = ParameterDirection.Input;
            moFrom1Param.SqlDbType = SqlDbType.DateTime;
            cmd.Parameters.Add(moFrom1Param);

当我执行此操作时,只给出某些参数的实际日期时间,其余的都为空.所以要明确的是,从星期一到星期三的所有参数都有一个日期时间值.周四休息,直到周日没有.所以那些传递为null.我收到这样的错误:

The parameterized query '(@tnrProfile int,@forwardMail bit,@forwardSms bit,@forwardMessag' expects the parameter '@ThFrom1', which was not supplied.

我在stackoverflow和google上找了一些答案,但我发现的答案从来没有对我有用..

所以我的问题是,我怎样才能确保如果我的DateTime参数的值为null,则该值由sql理解并实际传递为null而不是告诉我参数未提供.

希望有人在这里可以帮助我.

谢谢.

编辑:这是解决方案:

SqlParameter moFrom1Param = new SqlParameter("@MoFrom1", dTOForwarding.MoFrom1 == null ?
                (Object)DBNull.Value : dTOForwarding.MoFrom1);
            moFrom1Param.IsNullable = true;
            moFrom1Param.Direction = ParameterDirection.Input;
            moFrom1Param.SqlDbType = SqlDbType.DateTime;
            cmd.Parameters.Add(moFrom1Param);

Answer 1

SqlParameter moFrom1Param = new SqlParameter("@MoFrom1", dTOForwarding.MoFrom1 == null ? DBNull.Value : dTOForwarding.MoFrom1);
            moFrom1Param.IsNullable = true;
            moFrom1Param.Direction = ParameterDirection.Input;
            moFrom1Param.SqlDbType = SqlDbType.DateTime;
            cmd.Parameters.Add(moFrom1Param);

Answer 2

你试过DBNull.Value吗？

SqlParameter moFrom1Param;
if (dTOForwarding.MoFrom1 != null)
    moFrom1Param = new SqlParameter("@MoFrom1", dTOForwarding.MoFrom1);  
else
    moFrom1Param = new SqlParameter("@MoFrom1", DBNull.Value);  

此外,您的代码显示"@ MoFrom1",但错误与@ ThFrom1有关