Which is preferred: Nullable<T>.HasValue or Nullable<T> != null?

c# .net null nullable
lc. picture lc. · Mar 24, 2009 · Viewed 100.3k times · Source

I always used Nullable<>.HasValue because I liked the semantics. However, recently I was working on someone else's existing codebase where they used Nullable<> != null exclusively instead.

Is there a reason to use one over the other, or is it purely preference?

  1. int? a;
if (a.HasValue)
    // ...

vs.

  1. int? b;
if (b != null)
    // ...

Answer

Rex M picture Rex M · Mar 24, 2009

The compiler replaces null comparisons with a call to HasValue, so there is no real difference. Just do whichever is more readable/makes more sense to you and your colleagues.

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