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I've got a DateTime?
that I'm trying to insert into a field using a DbParameter
. I'm creating the parameter like so:
DbParameter datePrm = updateStmt.CreateParameter(); datePrm.ParameterName = "@change_date";
And then I want to put the value of the DateTime?
into the dataPrm.Value
while accounting for null
s.
I thought initially I'd be clever:
datePrm.Value = nullableDate ?? DBNull.Value;
but that fails with the error
Operator '??' cannot be applied to operands of type 'System.DateTime?' and 'System.DBNull'
So I guess that only works if the second argument is a non-nullable version of the first argument. So then I went for:
datePrm.Value = nullableDate.HasValue ? nullableDate.Value : DBNull.Value;
but that doesn't work either:
Type of conditional expression cannot be determined because there is no implicit conversion between 'System.DateTime' and 'System.DBNull'
But I don't want to convert between those types!
So far the only thing I can get to work is:
if (nullableDate.HasValue) datePrm.Value = nullableDate.Value; else datePrm.Value = DBNull.Value;
Is that really the only way I can write this? Is there a way to get a one-liner using the ternary operator to work?
Update: I don't really get why the ?? version doesn't work. MSDN says:
The ?? operator returns the left-hand operand if it is not null, or else it returns the right operand.
That's exactly what I want!
Update2: Well it was kind of obvious in the end:
datePrm.Value = nullableDate ?? (object)DBNull.Value;