Question

I have got an integer value and i need to check if it is NULL or not. I got it using a null-coalescing operator

C#:

public int? Age;

if ((Age ?? 0)==0)
{
   // do somethig
}

Now i have to check in a older application where the declaration part is not in ternary. So, how to achieve this without the null-coalescing operator.

Answer 1

Nullable<T> (or ?) exposes a HasValue flag to denote if a value is set or the item is null.

Also, nullable types support ==:

if (Age == null)

The ?? is the null coalescing operator and doesn’t result in a boolean expression, but a value returned:

int i = Age ?? 0;

So for your example:

if (age == null || age == 0)

Or:

if (age.GetValueOrDefault(0) == 0)

Or:

if ((age ?? 0) == 0)

Or ternary:

int i = age.HasValue ? age.Value : 0;