> Using C# 2.0 & SQL Server 2000, have a stored procedure that return 0, 1, or
> more rows.  At least one of the columns is a date and it may null.  I have
> created an XSD of the output from the stored proc.  The entry for the
> nullable date column is "<xs:element name="Sent_Dttm" minOccurs="0"
> type="xs:dateTime" nillable="true"></xs:element>".  I copied the XSD to the
> C# 2.0 windows app I am developing and it nicely generates a strongly typed
> dataset.
>
> The problem is I get an error when attempting to access this column in the
> dataset when the value is null:
> [System.Diagnostics.DebuggerNonUserCodeAttribute()]
>             public System.DateTime Sent_Dttm {
>                 get {
>                     try {
>                         return
> ((System.DateTime)(this[this.tableOwizCommDoc.Sent_DttmColumn]));
>                     }
>                     catch (System.InvalidCastException e) {
>                         throw new System.Data.StrongTypingException("The
> value for column \'Sent_Dttm\' in table \'OwizCommDoc\' is DBNull.", e);
>                     }
>                 }
>                 set {
>                     this[this.tableOwizCommDoc.Sent_DttmColumn] = value;
>                 }
>             }
>
>
> Checking the properties of this field, I noticed that the "NullValue"
> property has a value of "(throw exception)'
>
>
>
>

"Rachel Appel" <n***@example.com> wrote in message
news:MPG.218ac7a7b92c306989680@msnews.microsoft.com...
> In article <F82909CD-DEBB-457A-AC69-DED1C4D72***@microsoft.com>,
> RobertEFlahe***@discussions.microsoft.com says...
>> Using C# 2.0 & SQL Server 2000, have a stored procedure that return 0, 1,
>> or
>> more rows.  At least one of the columns is a date and it may null.  I
>> have
>> created an XSD of the output from the stored proc.  The entry for the
>> nullable date column is "<xs:element name="Sent_Dttm" minOccurs="0"
>> type="xs:dateTime" nillable="true"></xs:element>".  I copied the XSD to
>> the
>> C# 2.0 windows app I am developing and it nicely generates a strongly
>> typed
>> dataset.
>>
>> The problem is I get an error when attempting to access this column in
>> the
>> dataset when the value is null:
>> [System.Diagnostics.DebuggerNonUserCodeAttribute()]
>>             public System.DateTime Sent_Dttm {
>>                 get {
>>                     try {
>>                         return
>> ((System.DateTime)(this[this.tableOwizCommDoc.Sent_DttmColumn]));
>>                     }
>>                     catch (System.InvalidCastException e) {
>>                         throw new System.Data.StrongTypingException("The
>> value for column \'Sent_Dttm\' in table \'OwizCommDoc\' is DBNull.", e);
>>                     }
>>                 }
>>                 set {
>>                     this[this.tableOwizCommDoc.Sent_DttmColumn] = value;
>>                 }
>>             }
>>
>>
>> Checking the properties of this field, I noticed that the "NullValue"
>> property has a value of "(throw exception)'
>>
>>
>>
>>
>
> Robert,
> Try checking for System.DbNull before accessing the variable and that
> should help you out.

"Jim Rand" wrote:

> This is by design.  The strongly typed dataset will have a method (not
> property) IsSent_DttmNull() if the underlying column can be null.
>
> if (!IsSent_DttmNull) {access the value}
>
> "Rachel Appel" <n***@example.com> wrote in message
> news:MPG.218ac7a7b92c306989680@msnews.microsoft.com...
> > In article <F82909CD-DEBB-457A-AC69-DED1C4D72***@microsoft.com>,
> > RobertEFlahe***@discussions.microsoft.com says...
> >> Using C# 2.0 & SQL Server 2000, have a stored procedure that return 0, 1,
> >> or
> >> more rows.  At least one of the columns is a date and it may null.  I
> >> have
> >> created an XSD of the output from the stored proc.  The entry for the
> >> nullable date column is "<xs:element name="Sent_Dttm" minOccurs="0"
> >> type="xs:dateTime" nillable="true"></xs:element>".  I copied the XSD to
> >> the
> >> C# 2.0 windows app I am developing and it nicely generates a strongly
> >> typed
> >> dataset.
> >>
> >> The problem is I get an error when attempting to access this column in
> >> the
> >> dataset when the value is null:
> >> [System.Diagnostics.DebuggerNonUserCodeAttribute()]
> >>             public System.DateTime Sent_Dttm {
> >>                 get {
> >>                     try {
> >>                         return
> >> ((System.DateTime)(this[this.tableOwizCommDoc.Sent_DttmColumn]));
> >>                     }
> >>                     catch (System.InvalidCastException e) {
> >>                         throw new System.Data.StrongTypingException("The
> >> value for column \'Sent_Dttm\' in table \'OwizCommDoc\' is DBNull.", e);
> >>                     }
> >>                 }
> >>                 set {
> >>                     this[this.tableOwizCommDoc.Sent_DttmColumn] = value;
> >>                 }
> >>             }
> >>
> >>
> >> Checking the properties of this field, I noticed that the "NullValue"
> >> property has a value of "(throw exception)'
> >>
> >>
> >>
> >>
> >
> > Robert,
> > Try checking for System.DbNull before accessing the variable and that
> > should help you out.
>
>
>

"Cor Ligthert[MVP]" wrote:

> Robert,
>
> If a column allows nulls, then there is in your strongly typed dataset
> created a method named as IsTheFieldNameNull()
>
> If the DataBase does not allows Nulls, then it is of course a normal error.
>
> Cor
>