Re: Nullable types giving error

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"Arne Vajhøj" <arne@xxxxxxxxxx> wrote in message
news:47bf71e2$0$90263$14726298@xxxxxxxxxxxxxxxxxx
tshad wrote:
It depends. The type in SQL is tinyint. In my record fn.ProjectTableID
is an "int?". The value will either be null or a number from 1-25.

If it is null, which is the case for the first 12 records, I get the
following in the debugger watch window

{Name = "DBNull" FullName = "System.DBNull"} System.Type
{System.RuntimeType}

:If it is a value like 10, I get:

{Name = "Byte" FullName = "System.Byte"} System.Type {System.RuntimeType}
^^^^^^^^^^^

I would assume that I would be casting it to either int? or int since I
am putting it in an int? field. I can't change the fn.ProjectTableID to
int (or byte) as it can be null and I need to keep track of that.

Try cast it to byte.

That works fine.

Since a tinyint ranges from 0 to 255, I assume that is why it is assumed to
be a byte.

fn.ProcessingType = dbReader["ProcessingType"] == DBNull.Value ? null :
(byte?)dbReader["ProcessingType"];

This works ok

I would have assumed that int would also work but I guess not.

Thanks,

Tom

Arne


.

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