From Microsoft: The Visual Studio Async CTP (Version 3) extends Visual Studio 2010, providing a new, streamlined syntax for asynchronous development.
Questions tagged [async-ctp]
168 questions
342
votes
14 answers
How to call an async method from a getter or setter?
What'd be the most elegant way to call an async method from a getter or setter in C#?
Here's some pseudo-code to help explain myself.
async Task MyAsyncMethod()
{
return await DoSomethingAsync();
}
public IEnumerable MyList
{
…

Doguhan Uluca
- 6,933
- 4
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- 51
146
votes
4 answers
What's the difference between returning void and returning a Task?
In looking at various C# Async CTP samples I see some async functions that return void, and others that return the non-generic Task. I can see why returning a Task is useful to return data to the caller when the async operation completes,…

James Cadd
- 12,136
- 30
- 85
- 134
137
votes
5 answers
Using async-await on .net 4
I'm currently starting to create an application that would profit a lot from C# 5's async-await feature. But I'm not sure which version of VS and of the async runtime to use.
Looking at OS popularity charts, I'll need to support Windows XP for…

CodesInChaos
- 106,488
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86
votes
14 answers
Task<> does not contain a definition for 'GetAwaiter'
Client
iGame Channel = new ChannelFactory ( new BasicHttpBinding ( BasicHttpSecurityMode . None ) , new EndpointAddress ( new Uri ( "http://localhost:58597/Game.svc" ) ) ) . CreateChannel ( );
public Task Client (…

Ahmed Ghoneim
- 6,834
- 9
- 49
- 79
74
votes
2 answers
can not await async lambda
Consider this,
Task task = new Task (async () =>{
await TaskEx.Delay(1000);
});
task.Start();
task.Wait();
The call task.Wait() does not wait for the task completion and the next line is executed immediately, but if I wrap the async lambda…

kennyzx
- 12,845
- 6
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- 83
70
votes
3 answers
Why use async requests instead of using a larger threadpool?
During the Techdays here in the Netherlands Steve Sanderson gave a presentation about C#5, ASP.NET MVC 4, and asynchronous Web.
He explained that when requests take a long time to finish, all the threads from the threadpool become busy and new…

Wouter de Kort
- 39,090
- 12
- 84
- 103
45
votes
4 answers
Why does the async keyword exist
Browsing through the channel 9 msdn videos I found the following unanswered comment and was hoping someone could possibly explain it?
I dont get the point of the async keyword. Why not just allow the
await keyword anytime the method returns…

Maxim Gershkovich
- 45,951
- 44
- 147
- 243
40
votes
3 answers
CancellationToken UnRegister Action
I have a token for various tasks and I need to better manage their cancellation, to be notified of a cancellation I can use:
token.Register(RegisterMethod);
How can I remove this "subscription"?
Is there any way to "UnRegister"?
I thought about…

J. Lennon
- 3,311
- 4
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- 64
22
votes
2 answers
What happens to an `awaiting` thread in C# Async CTP?
I've been reading about the new async await keyword and it sounds awesome, but there is one key question I haven't been able to find the answer for in any of the intro videos I've watched so far (I also read the whitepaper a while back).
Suppose I…

devios1
- 36,899
- 45
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21
votes
1 answer
Is async recursion safe in C# (async ctp/.net 4.5)?
In C# with async ctp or the vs.net 2011 beta we can write recursive code like this:
public async void AwaitSocket()
{
var socket = await this.AcceptSocketAsync(); //await socket and >>return<< to caller
AwaitSocket(); //recurse, note that…

Roger Johansson
- 22,764
- 18
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20
votes
2 answers
Async CTP and "finally"
Here's the code:
static class AsyncFinally
{
static async Task Func( int n )
{
try
{
Console.WriteLine( " Func: Begin #{0}", n );
await TaskEx.Delay( 100 );
Console.WriteLine( " …

Soonts
- 20,079
- 9
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20
votes
3 answers
Run an async function in another thread
I'm evaluating the Async CTP.
How can I begin execution of an async function on another thread pool's thread?
static async Task Test()
{
// Do something, await something
}
static void Main( string[] args )
{
// Is there more elegant way to…

Soonts
- 20,079
- 9
- 57
- 130
17
votes
3 answers
Code Contracts and Asynchrony
What is the recommended way for adding postconditions to async methods which return Task?
I have read the following suggestion:
http://social.msdn.microsoft.com/Forums/hu-HU/async/thread/52fc521c-473e-4bb2-a666-6c97a4dd3a39
The post suggests…

Lawrence Wagerfield
- 6,471
- 5
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- 84
17
votes
3 answers
How to write simple async method?
Using latest CTP5 with async/await keywords, I wrote some code, which apparently cannot compile:
class Program
{
public class MyClass
{
async public Task Test()
{
var result = await…

ghord
- 13,260
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16
votes
4 answers
Why was "SwitchTo" removed from Async CTP / Release?
I tried to use the SwitchTo method today to switch to the GUI thread, and found that the example I lifted it from does not work, simply because the method is not there.
I then found this blurb here:
The reason we got rid of it was because it was so…

Lasse V. Karlsen
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