Class ObservableExtensions

Namespace: Cratis.Reactive

Assembly: Cratis.Fundamentals.dll

Holds extension methods for System.Reactive.Subjects.ISubject<T>.

public static class ObservableExtensions

Inheritance: object

ObservableExtensions

Inherited Members: object.GetType()

object.MemberwiseClone()

object.ToString()

object.Equals(object)

object.Equals(object, object)

object.ReferenceEquals(object, object)

object.GetHashCode()

Methods

CompletedBy<TResult>(ISubject<TResult>, CancellationToken)

Completes the subject when the CancellationToken is cancelled.

public static ISubject<TResult> CompletedBy<TResult>(this ISubject<TResult> subject, CancellationToken cancellationToken)

Parameters

subject ISubject<TResult>: The subject to complete.
cancellationToken CancellationToken: The cancellation token to observe.

Returns

ISubject<TResult>: The subject.

Type Parameters

TResult: Type of result.

InvokeAndWrapWithSubject<TResult>(object, Func<CancellationToken, IObservable<TResult>>)

Invokes an action and wraps the observable result in a subject providing, with a cancellation token passed to the action that cancels when the subject is completed.

public static ISubject<TResult> InvokeAndWrapWithSubject<TResult>(this object instance, Func<CancellationToken, IObservable<TResult>> action)

Parameters

instance object: The instance to extend.
action Func<CancellationToken, IObservable<TResult>>: The action to invoke that returns an observable.

Returns

ISubject<TResult>: The subject.

Type Parameters

TResult: Type of result.

Remarks

The returned subject replays its most recent value to whoever subscribes to it. Callers wrap an observable here and hand the subject on to a consumer that subscribes later, so a source emitting synchronously while it is being subscribed - a System.Reactive.Subjects.BehaviorSubject<T> seed, a System.Reactive.Subjects.ReplaySubject<T> buffer, anything backed by in-memory state - would otherwise emit into a subject nobody is listening to yet and the value would be lost for good.

InvokeAndWrapWithTransformSubject<TResult, TSource>(object, Func<CancellationToken, IObservable<TSource>>, Func<TSource, TResult>)

Invokes an action and wraps the observable result in a subject providing, with a cancellation token passed to the action that cancels when the subject is completed.

public static ISubject<TResult> InvokeAndWrapWithTransformSubject<TResult, TSource>(this object instance, Func<CancellationToken, IObservable<TSource>> action, Func<TSource, TResult> transform)

Parameters

instance object: The instance to extend.
action Func<CancellationToken, IObservable<TSource>>: The action to invoke that returns an observable.
transform Func<TSource, TResult>: The transform to apply to the observable result.

Returns

ISubject<TResult>: The subject.

Type Parameters

TResult: Type of result.
TSource: Type of source.

Remarks

The returned subject replays its most recent value - see InvokeAndWrapWithSubject<TResult>(object, Func<CancellationToken, IObservable<TResult>>) for why.