Question

In the below sample code, I have tried to use Nullable(of T) for DateTime and I want to use it same of the Dimensions property which is List(of Dimension).

 Private _duedate As Nullable(Of DateTime)
        Public Property DueDate() As Nullable(Of DateTime)
            Get
                Return _duedate
            End Get
            Set(ByVal value As Nullable(Of DateTime))
                _duedate = value
            End Set
        End Property

   Private _dimensions As List(Of Dimension)
            Public Property Dimensions() As List(Of Dimension)
                Get
                    Return _dimensions
                End Get
                Set(ByVal value As List(Of Dimension))
                    _dimensions = value
                End Set
            End Property

If we can then please any help on how can we do it would be appreciated.

Thanks.

Answer 1

There is no need to use Nullable(Of T) for List(Of T). Simply use List(Of T) directly and use Nothing for the no value state.

The basic capability Nullable(Of T) provides is for value types to have a no-value state. This concept is clearer in C# where there is a syntactic difference between no value null and default value default(T). In VB.Net though there is simply Nothing which represents both no value for reference types and default value for value types.