And, Lucian has another talk about Async at DevConnections, was that recorded ?

posted by felix9

When using the "traditional" methods, the game it background continued to play, but when demo the Async approach, it seem (to me) to run synchronously. ie the Message Popup appeared then the game ran. 

Was this an artefact of  Async, the rest of code following this is lifted into a continuation?

posted by AdamSpeight2008

You can watch it here (since it's screen capture + audio, I'm supplying links to the high quality media below) :

HQ WMV: http://media.ch9.ms/ch9/b8c8/c31a592d-42d3-4e65-810f-a41280b0b8c8/LucianWischikAsync_Source.wmv

HQ MP4: http://media.ch9.ms/ch9/b8c8/c31a592d-42d3-4e65-810f-a41280b0b8c8/LucianWischikAsync_high.mp4

C

posted by Charles

@Felix: in addition to the video of the async talk, there are also the slides and script and source code on my blog: http://blogs.msdn.com/b/lucian/archive/2012/03/29/talk-async-part-1-the-message-loop-and-the-task-type.aspx (The audio quality is terribly for the first few minutes, but gets a little better...)

@Adam: Yes precisely: the await keyword lifted everything else into the continuation...

In the traditional code I wrote
op1 = New MessageDialog("hello").ShowAsync()
op1.Completed = Sub() Dispatcher.InvokeAsync(Sub()
    op2 = New MessageDialog("world").ShowAsync()
End Sub)
PlayRestOfGame()

Note that "PlayRestOfGame" was started immediately after the first dialogbox appeared.

Meanwhile, in the await code, I wrote
Await New MessageDialog("hello").ShowAsync()
Await New MessageDialog("world").ShowAsync()
PlayRestOfGame()

This caused the rest of the game to start only after the second dialog had finished.

Could I have written traditional code to play the game only after the second dialog had finished? Yes, I'd do it with "op2.Completed = Sub() PlayRestOfGame()"

Could I have written the async code to play the game while the dialogs were still doing there stuff? Yes, I might do something like this:
Dim background_task = ShowDialogsAsync() ' kick off the dialogs
PlayRestOfGame()  ' but, without awaiting it, let's just get on with the game

Async Sub ShowDialogsAsync()
   Await New MessageDialog("hello").ShowAsync()
   Await New MessageDialog("world").ShowAsync()
End Sub

posted by ljw1004

posted by Doctor Who

ByVal is implicit now: if you omit ByVal/ByRef, then the compiler treats the parameter as ByVal. If you want anything passed by reference, you still need ByRef. Other than that, it's exactly how it always was.

It's hard to answer your individual questions directly since the answers are more confusing than enlightening... ("What do you mean you're passing my reference by value?!?!!"). Nevertheless: by default everything is passed by value; String objects are immutable references and like all references they are by default passed by value; when you pass a reference to a regular reference-type, the reference is passed by value; if you want to pass a value-type by reference then yes you use ByRef.

@Matt:

Absolutely. We've already said that we're committed to VB. And you can see we're putting our money where our mouth is -- with the huge slate of new features in VB11, with the exciting developments forthcoming in Roslyn, and with all the new platforms that are supporting VB (including most recently Gadgeteer). My personal opinion is that if a professional .NET developer claims they can't read C# or VB or F#, then I'd hesitate to call them a professional...

posted by ljw1004

posted by Doctor Who