C# - Comparing Nullable DateTime's In VB.net?

Nov 17, 2010

I am a c#/asp.net developer and I am having to work on a VB/asp.net. I started out with VB.NET but after years away from it I'm getting confused with the syntax.

I have two variables

Dim originalDate as DateTime?
Dim newDate as DateTime?

Both nullable datetimes, originalDate is a nullable date I am getting from the database and newDate time is set in code, I need to compare them, they can either both have dates, neither have dates or one have and one not.

I have a bit of code as follows:

if origEndDate = origEndDate then

When both origEndDate and origEndDate are "nothing" this statement is false (well when I run it in the watch window it comes back as nothing)!

I don't understand why this is the case because I was under the impression doing an "=" compares the two values and as they are the same surely it should be true?

What syntax should I be using as in C# I can do the above as so:

if (origEndDate == origEndDate) { }

and it will come back as true.

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