getawaiter().getresult() vs result|Long Story Short: Async/Await Best Practices in .NET

getawaiter().getresult() vs result,When you write “ await task; ”, the compiler translates that into usage of the Task.GetAwaiter() method, which returns an instance that has a GetResult() method. When used on a faulted Task, GetResult() will propagate the original exception (this is how “ await task; ” gets its behavior). When you use Task.Run, the initial synchronous part of your delegate is run on a threadpool thread, whereas just ().GetAwaiter().GetResult() will run that synchronous part on . But the better way is using the .Getawaiter ().GetResult (). Why? It’s about the exception trace and exception handle.In those rare conditions, my preferred method is GetAwaiter().GetResult() because it preserves the task exceptions instead of wrapping them in an AggregateException. And GetResult is used to retrieve the result of the operation, such that after the operation completes, the awaiter can either get the TResult or propagate any exception that .getawaiter().getresult() vs result Long Story Short: Async/Await Best Practices in .NET If you are using ".GetAwaiter ().GetResult ()", ".Result" or ".Wait ()" to get the result of a task or to wait for the task completion you may experience deadlocks or thread .

One small difference though: if the Task fails, GetResult() will just throw the exception caused directly, while Task.Result will throw an AggregateException.Gets an awaiter used to await this Task. public: System::Runtime::CompilerServices::TaskAwaiter GetAwaiter (); C#. Copy. public . Avoid using .Wait () or .Result — Use GetAwaiter ().GetResult () instead If you have to block waiting the completion of an Async Task, use GetAwaiter ().GetResult ().

getawaiter().getresult() vs result GetAwaiter() not waits for task, just returns TaskAwaiter object, which can be used to wait for task by calling GetResult().So calling GetAwaiter() only is meaningless. As documentation states this class is only intended of compiler use and users should not use it. You should use Task.Wait(), when you want to wait for task, but not need result.But sometimes .

閱讀筆記 - 使用 .NET Async/Await 的常見錯誤提到「需要等待結果才繼續執行的場合，宜用 .GetAwaiter().GetResult() 取代 .Result」，這點喚起我過去寫非同步程式的回憶：設了 try catch 也捕捉到錯誤，但回拋的錯誤訊息 .

HOWEVER, I'd still like to know why the ConfigureAwait.GetAwaiter.GetResult pattern is giving me trouble. My understanding was that GetAwaiter.GetResult was a way to call async method from syncronous methods when changing the signature is not an option.

The GetAwaiter().GetResult() method call is equivalent to calling Task.Wait() method and Task.Result. However, the difference is that GetAwaiter().GetResult() is preferred to the latter because it propagates exceptions instead of wrapping them in an AggregateException. Let’s add a method that calls the GetPeopleAsync() method .

public System.Runtime.CompilerServices.TaskAwaiter GetAwaiter (); member this.GetAwaiter : unit -> System.Runtime.CompilerServices.TaskAwaiter Public Function GetAwaiter As TaskAwaiter Returns. TaskAwaiter. An awaiter instance. Remarks. This method is intended for compiler use rather than use directly in code. Async/await was added to the C# language over a decade ago and has transformed how we write scalable code for .NET. But how does it really work? In this post, we take a deep dive into its internals. Using .GetAwaiter().GetResult() when the operation hasn’t yet completed. The IValueTaskSource / IValueTaskSource implementation need not support blocking until the operation completes, and likely doesn’t, so such an operation is inherently a race condition and is unlikely to behave the way the caller intends. I try to understand the concept between GetAwaiter().GetResult().I know that it shouldn't be used if possible but I cannot use async/await in this case so I must get the result from an asynchronous function in a synchronous matter.

Invoked method immediately returns to the caller (i.e. to the Main) on first await and from there, both (the caller and the invoked method) run concurrently. Yet, since the Main finishes first, the whole program ends.. Thus, if you want to wait for asynchronous call completion you may change Create() to return Task rather than void and then you can wait such as: .

I am trying to understand why the following Task.Run and GetAwaiter().GetResult() would be used instead of await . (var success, var response) = Task.Run(() => HTTPHelper.SendRequest( . )).GetAwaiter().GetResult(); Does the code above throw, as this article shows, an Exception .On the other hand, for ValueTask it was much more slower so I stayed with.Result for VT." And so, from the code that we will be writing, we should see that .Result should provide us with the best performance when working with a ValueTask. And GetAwaiter.GetResult() should give us the best performance when working with a Task. "The GetAwaiter().GetResult()" will do the same" - no, it does not "do the same but synchronously" thing as await: the thread calling GetResult() does not yield itself to the thread-pool: the thread is blocked instead. – 結論. Wait()は良くある別タスク内で発生した例外同様AggreateExceptinoでまとめてChatchされる。 一方でGetAwaiter().GetResult()は同期メソッドで例外が発生したかの如く、発生時の状態で補足される。Both Task.Wait and Task.Result are blocking and may also cause deadlocks and on top of that they also wrap exceptions in an AggregateException.. Now if you are in a situation where you can't use async/await and you have to do sync over async, the preferred way to do it seems to be Task.GetAwaiter().GetResult(); which can still cause deadlocks but at least it doesn't wrap .

If we comment the line mentioned and uncomment thing.CallingAsync().GetAwaiter().GetResult() the results change: This is an argument exception Message: Hey, this is an exception Stack: at AwaitForMe.TheThing.Receiving . 从这个角度说Task.GetAwaiter().GetResult()要优于Task.Result。毕竟它少了异常的包装操作，即直接抛出异常，而不是把异常包装在AggregateException中。 下面的引言解释了为什么Task.Result不仅仅包含Task.GetAwaiter().GetResult()（由于“非常高的兼容性”）的异常传 .Long Story Short: Async/Await Best Practices in .NET task.Result; task.GetAwaiter().GetResult() Use a try-catch statement to handle and observe thrown exceptions. Alternatively, observe the exception by accessing the Task.Exception property. Important. The AggregateException cannot . 如果任务失败， Task.GetAwaiter().GetResult()会直接抛出异常 ， 而Task.Result则会把异常包装在AggregateException中 。 从这个角度说Task.GetAwaiter().GetResult()要优于Task.Result。 毕竟它少了异常的包装操作，即直接抛出异常，而不是把异常包装在AggregateException中。

getawaiter().getresult() vs result|Long Story Short: Async/Await Best Practices in .NET

getawaiter().getresult() vs result|Long Story Short: Async/Await Best Practices in .NET .

Share:

×

Share

Copy Link

Email

Facebook

Twitter

LinkedIn

WhatsApp

Download: Full Size (80225 MB)

Photo By: getawaiter().getresult() vs result|Long Story Short: Async/Await Best Practices in .NET

VIRIN: 44523-50786-27744