Construtor T> AsyncSubject<
Inicializa uma nova instância da classe T> AsyncSubject<.
Namespace:System.Reactive.Subjects
Assembly: System.Reactive (em System.Reactive.dll)
Sintaxe
'Declaration
Public Sub New
'Usage
Dim instance As New AsyncSubject()
public AsyncSubject()
public:
AsyncSubject()
new : unit -> AsyncSubject
public function AsyncSubject()
Exemplos
Neste exemplo, um AsyncSubject é usado para assinar uma sequência de inteiros gerada com o operador Range. Um AsyncSubject retorna apenas um valor quando a sequência à qual está inscrito é concluída. Depois que a sequência for concluída, o AsyncSubject publicará o item final na sequência. O AsyncSubject armazena em cache o item final. Todas as novas assinaturas em relação a esse AsyncSubject também terão o item final publicado nessa assinatura.
using System;
using System.Reactive.Linq;
using System.Reactive.Subjects;
using System.Reactive.Concurrency;
using System.Threading;
namespace Example
{
class Program
{
static void Main()
{
//*******************************************************************************************************//
//*** A subject acts similar to a proxy in that it acts as both a subscriber and a publisher ***//
//*** It's IObserver interface can be used to subscribe to multiple streams or sequences of data. ***//
//*** The data is then published through it's IObservable interface. ***//
//*** ***//
//*** In this example an AsyncSubject is used to subscribe to an integer sequence from the Range ***//
//*** operator. An AsyncSubject only returns a value when the sequence it is subscribed to completes. ***//
//*** Once the sequence has completed, the AsyncSubject will publish the final item in the sequence. ***//
//*** The AsyncSubject caches the final item. Any new subscriptions against that AsyncSubject will ***//
//*** also have the final item published to that subscription as well. ***//
//*******************************************************************************************************//
var intSequence = Observable.Range(0, 10, Scheduler.ThreadPool);
AsyncSubject<int> myAsyncSubject = new AsyncSubject<int>();
intSequence.Subscribe(myAsyncSubject);
Thread.Sleep(1000);
myAsyncSubject.Subscribe(i => Console.WriteLine("Final integer for subscription #1 is {0}\n", i),
() => Console.WriteLine("subscription #1 completed.\n"));
Console.WriteLine("Sleeping for 5 seconds before subscription2\n");
Thread.Sleep(5000);
myAsyncSubject.Subscribe(i => Console.WriteLine("Final integer for subscription #2 after 5 seconds is {0}\n", i),
() => Console.WriteLine("subscription #2 completed.\n"));
Console.WriteLine("Press ENTER to exit...");
Console.ReadLine();
myAsyncSubject.Dispose();
}
}
}
A saída a seguir foi gerada pelo código de exemplo.
Final integer for subscription #1 is 9
subscription #1 completed.
Sleeping for 5 seconds before subscription2
Final integer for subscription #2 after 5 seconds is 9
subscription #2 completed.
Press ENTER to exit...