Is it right to cast null to nullable when using ternary expression assigning to a nullable type?

Question

It feels strange to me to be casting null to a type so I wanted to double check that this is the right way to do this:

decimal? d = data.isSpecified ? data.Value : (decimal?)null;

NOTE: I am marking the answer that suggests the method that I personally like the best:

decimal? d = data.isSpecified ? data.Value : default(decimal?)

Answer 1

Yes, it is perfectly fine.

Answer 2

Is data.Value of type decimal? If so, here's an alternative notation, without the cast:

decimal? d = data.isSpecified ? new decimal?(data.Value) : null;

Answer 3

Yes, that's fine. Alternatives:

condition ? (decimal?) value : null

condition ? new decimal?(value) : null

condition ? value : default(decimal?)

condition ? value : new decimal?()

Pick whichever you find most readable.

There's nothing you can do outside the expression itself, as it's the type of the expression which the compiler doesn't know. For example, putting the whole expression in brackets and casting it wouldn't help.