Is there any difference between type? and Nullable<type>?

If you look at the IL using Ildasm, you'll find that they both compile down to Nullable<bool>.

There is no difference between bool? b = null and Nullable<bool> b = null. The ? is just C# compiler syntax sugar.

To access the value of the bool? you need to do the following:

bool? myValue = true;
bool hasValue = false;

if (myValue.HasValue && myValue.Value)
{
  hasValue = true;
}

Note you can't just do:

if (myValue)
{
  hasValue = true;
}

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