Hi There,
I was wondering if there are some best practices for handling null value assigments for properties.

For instance, how would I get to following property to accept a null value returned from the database, so I can assign the property value after I instantiated the class?

    Public Property Date_Start() As DateTime Implements Task._Date_Start
        Get
            Return _Date_Start
        End Get
        Set(ByVal value As DateTime)
            _Date_Start = value
        End Set
    End Property

'below gets an error in the class method when retrieving the instance
_Date_Start = prmDate_Start.Value


Thanks for your help.

Paul Olofson

Hi there,

.NET 2 has introduced the concepts of a nullable type, allowing you to assign null to a DateTime.

http://blogs.msdn.com/vbteam/archive...28/143813.aspx
http://msdn.microsoft.com/vcsharp/20...nullabletypes/

Alternatively, and that's how I often did it in .NET 1.x applications, you can sign it a sensible "nullable in your opinion" default value, like DateTime.MinValue.

Then you can compare against MinValue and it the date is still MinValue you can assume it's null. However, the Nullable type is of course much cleaner.

HtH,

Imar
---------------------------------------
Imar Spaanjaars
Everyone is unique, except for me.
Author of ASP.NET 2.0 Instant Results and Beginning Dreamweaver MX / MX 2004
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