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New VB11 Features

13 October 2011

7 Comments

Posted by AdamSpeight2008

New VB11 Features

A preview of some of the new features coming in VB11, which you can experiment with via the VS11 Developer Preview

The New Features

Async & Await
This will be the major feature of VB11 asynchronous method supported directly by the language.

Module Module1
  Sub Main
    Dim SourceCode = GetSourceCode()
    Console.WriteLine(SourceCode)

  End Sub

  Public Async Function GetSourceCode() As Task(Of String)
    Return Await (New Net.WebClient).DownloadStringTaskAsync("www.dreamincode.net")
   End Function
End Module

The infrastructure used in the Async & Await enables VB.net to have a Yield keyword like c#. This allows us to use Iterators.

Iterators
You can implement Iterator various ways, through the use of the Yield keyword

Functions

  Public Iterator Function OneToHundred() As IEnumerable(Of Integer)
    For x = 1 To 100
      Yield x
    Next
  End Function

Lambdas

   Dim numbers_1_To_100 = Iterator Function()
                             For x = 1 To 100
                               Yield x
                             Next
                           End Function

Property (Strange but completes the list.)

  Public ReadOnly Iterator Property Strange() As IEnumerable(Of Integer)
    Get
      For x = 1 To 100
        Yield x
      Next
    End Get
  End Property

Iterator Lambdas (VB.net only)

  Dim numbers_1_To_100 = Iterator Function()
                             For x = 1 To 100
                               Yield x
                             Next
                           End Function

Namespace Global.
Usually everything you write inside your project is enclosed inside a base namespace (typically the name of the project.) Sometime there situations where you need "escape" the behavior

Namespace Global.Numbers
  <HideModuleName> Public Module Numbers
    Public Function Naturals() As IEnumerable(Of Integer)
      Return (Iterator Function()
                Dim x = 0
                While x < Integer.MaxValue
                  Threading.Interlocked.Increment(x)
                  Yield x
                End While
                Yield Integer.MaxValue
              End Function)()
    End Function
  End Module

End Namespace

Which can, along side Iterators let me write a single function (above) the returns an IEnumerable containing the natural integer numbers (Whole Number starting from 1, up to the Integer.MaxValue)

Imports Numbers
Module Module1

  Sub Main()
    Dim Total = Naturals.Take(100).Where(Function(x) (x Mod 3) = 0 OrElse (x Mod 5 = 0)).Sum
  End Sub

Categories: Async & Await, VB11, Uncategorized

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7 Comments On This Entry

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Amrykid

14 October 2011 - 07:00 AM

I'm looking forward to these features.

Tryparse

14 October 2011 - 07:35 AM

Thanks for the preview ... I'm still waiting for our shop to upgrade to .Net 4 :whatsthat:

Yo!

14 October 2011 - 12:46 PM

It's just a small thing but I like that they have the ribon control now

Curtis Rutland

14 October 2011 - 02:54 PM

I don't think Iterator Properties are all that strange. Properties are just fancy groups of specific methods. If there's such thing as an iterator method, why not an iterator property?

Yo!

14 October 2011 - 09:37 PM

Sorry, I had read somewhere that the ribbon control was a new control added in but I just installed the Preview and noticed that it wasn't really there.
Sorry to mislead you. :stupid:

AdamSpeight2008

15 October 2011 - 09:55 AM

@Curtis Rutland: What I thought as strange was more concept of what it would mean to set an Iterator Property, Iterator are should on that fact you can Yield values from them, so in the Set what would be the equivalent of a yield?

In reality the Setter take in an IEnumerable(Of ?? ).

AdamSpeight2008

15 October 2011 - 09:55 AM

Like so

Public Class Tt
  Public Iterator Property W() As IEnumerable(Of Integer)
    Get
      Yield 1
    End Get
    Set(value As IEnumerable(Of Integer))

    End Set
  End Property
End Class

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