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VB.NET null coalescing operator? [duplicate]

Possible Duplicates:
Coalesce operator and Conditional operator in VB.NET
Is there a VB.NET equivalent for C#'s ?? operator?

Is there a built-in VB.NET equivalent to the C# null coalescing operator?

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RiddlerDev Avatar asked Jul 22 '11 16:07

RiddlerDev


2 Answers

Yes, there is, a long as you're using VB 9 or later (included with Visual Studio 2008).

You can use the version of the If operator overloaded to accept only two arguments:

Dim myVar? As Integer = Nothing
Console.WriteLine(If(myVar, 7))

More information can be found here in a blog post by the VB.NET team.

(Yes, this is an operator, even though it looks like a function. It will compile down to the same IL as the "proper" null-coalescing operator in C#.)

Example

Dim b As Boolean?
Console.WriteLine("{0}.", If(b, "this is expected when b is nothing"))
'output: this is expected when b is nothing.

b = False
Console.WriteLine("{0}.", If(b, "this is unexpected when b is false"))
'output: False.

b = True
Console.WriteLine("{0}.", If(b, "this is unexpected when b is true"))
'output: True.
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Cody Gray Avatar answered Oct 01 '22 10:10

Cody Gray


According to this question it would seem the answer is If()

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SeeSharp Avatar answered Oct 01 '22 11:10

SeeSharp