Documentation of 'Property of class preceded by question mark'

Question

I have class that uses a ulong ParentId { get; set; }and I needed it to be nullable. Because if the entity (of this class) is added to the database, and has no parent, it must be null and not 0. So I remembered vaguely something about preceding it with a question mark. And it works. See the code below.

class ExampleClass
{
    public ulong ?ParentId { get; set; }
}

Question: Does anyone know where to find the documentation for this?

score 1 · Accepted Answer · answered Aug 07 '13 at 07:14

1

You may check Using Nullable Types and Nullable Types

answered Aug 07 '13 at 07:14

Giannis Paraskevopoulos

18,261
1
49
69

Marked as answer because more documentation provided. – Mike de Klerk Aug 07 '13 at 07:31

score 1 · Answer 2 · answered Aug 07 '13 at 07:14

1

For value type which can be nullable - http://msdn.microsoft.com/en-us/library/b3h38hb0.aspx Question mark after a value type is same as Nullable<T>

answered Aug 07 '13 at 07:14

tray2002

188
6

Documentation of 'Property of class preceded by question mark'

2 Answers2