BehaviorSubject<T>. Método Dispose
Cancelar a assinatura de todos os observadores e liberar recursos.
Namespace:System.Reactive.Subjects
Assembly: System.Reactive (em System.Reactive.dll)
Sintaxe
'Declaration
Public Sub Dispose
'Usage
Dim instance As BehaviorSubject
instance.Dispose()
public void Dispose()
public:
virtual void Dispose() sealed
abstract Dispose : unit -> unit
override Dispose : unit -> unit
public final function Dispose()
Implementações
Exemplos
Este exemplo demonstra o BehaviorSubject. O exemplo usa o operador Interval para publicar um inteiro em uma sequência de inteiros a cada segundo. A sequência será concluída pelo operador Take depois que 10 inteiros forem publicados. Essa é a sequência na qual o BehaviorSubject assina.
Duas assinaturas são criadas para a interface IObservable do BehaviorSubject para mostrar como ela publica seus dados.
Assinatura nº 1 : essa assinatura começará no início e mostrará o valor inicial armazenado em buffer do construtor (-9) na sequência.
Assinatura nº 2 : essa assinatura será iniciada após uma suspensão de 5 segundos. Esta assinatura mostra que a sequência começa com o item armazenado em buffer no momento.
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. ***//
//*** ***//
//*** A BehaviorSubject buffers the last item it published through its IObservable interface. If no ***//
//*** item has been published through its IObservable interface then the initial item provided in the ***//
//*** constructor is the current buffered item. When a subscription is made to the BehaviorSubject's ***//
//*** IObservable interface, the sequence published begins with the currently buffered item. ***//
//*** ***//
//*** No items are buffered or published from a BehaviorSubject once its IObserver interface receives ***//
//*** a completion. ***//
//*** ***//
//*** In this example, we use the Interval operator to publish an integer to a integer sequence every ***//
//*** second. The sequence will be completed by the Take operator after 10 integers are published. ***//
//*** This will be the sequence that the BehaviorSubject subscribes to. ***//
//*** ***//
//*** We will create 2 subscriptions to the BehaviorSubject's IObservable interface to show how it ***//
//*** publishes it's data. ***//
//*** ***//
//*** Subscription #1 : This subscription will start at the very beginning and will show the initial ***//
//*** buffered value from the constructor (-9) in the sequence. ***//
//*** ***//
//*** Subscription #2 : This subscription will start after a 5 sec. sleep showing the sequence starts ***//
//*** with the currently buffered item. ***//
//********************************************************************************************************//
BehaviorSubject<long> myBehaviorSubject = new BehaviorSubject<long>((-9));
Observable.Interval(TimeSpan.FromSeconds(1), Scheduler.ThreadPool).Take(10).Subscribe(myBehaviorSubject);
//********************************************************************************************************//
//*** Subscription #1 : This subscription will start at the very beginning and will show the initial ***//
//*** buffered value from the constructor (-9) in the sequence. ***//
//********************************************************************************************************//
EventWaitHandle wait1 = new EventWaitHandle(false, EventResetMode.ManualReset);
myBehaviorSubject.Subscribe(x => Console.WriteLine("Subscription #1 observes : " + x),
() =>
{
Console.WriteLine("Subscription #1 completed.");
wait1.Set();
});
//********************************************************************************************************//
//*** Subscription #2 : This subscription will start after a 5 sec. sleep showing the sequence starts ***//
//*** with the currently buffered item. ***//
//********************************************************************************************************//
Thread.Sleep(5000);
EventWaitHandle wait2 = new EventWaitHandle(false, EventResetMode.ManualReset);
myBehaviorSubject.Subscribe(x => Console.WriteLine("{0,30}Subscription #2 observes : {1}", " ", x),
() =>
{
Console.WriteLine("{0,30}Subscription #2 completed.", " ");
wait2.Set();
});
//**************************************************//
// *** Wait for completion on both subscriptions ***//
//**************************************************//
WaitHandle.WaitAll(new WaitHandle[] { wait1, wait2 });
myBehaviorSubject.Dispose();
Console.WriteLine("\nPress ENTER to exit...");
Console.ReadLine();
}
}
}
A saída a seguir do código de exemplo mostra as assinaturas sobrepostas.
Subscription #1 observes : -9
Subscription #1 observes : 0
Subscription #1 observes : 1
Subscription #1 observes : 2
Subscription #1 observes : 3
Subscription #1 observes : 4
Subscription #2 observes : 4
Subscription #1 observes : 5
Subscription #2 observes : 5
Subscription #1 observes : 6
Subscription #2 observes : 6
Subscription #1 observes : 7
Subscription #2 observes : 7
Subscription #1 observes : 8
Subscription #2 observes : 8
Subscription #1 observes : 9
Subscription #2 observes : 9
Subscription #1 completed.
Subscription #2 completed.
Press ENTER to exit...