,System.Func{--0,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask{--1}})} ,System.Func{--0,--1})}

ObservableAsync.Select(IObservableAsync, Func>) method¶

Defined in

Type: ObservableAsync Namespace: ReactiveUI.Extensions.Async Assembly: ReactiveUI.Extensions.dll

Applies to

net10.0, net10.0-browserwasm1.0, net10.0-desktop1.0, net9.0, net9.0-browserwasm1.0, net9.0-desktop1.0, net8.0, net8.0-ios17.5, net8.0-maccatalyst17.5, net8.0-macos14.2, net8.0-macos14.5, net8.0-tvos17.2, netstandard2.1, net462, net481

Overloads¶

1. public static IObservableAsync<TDest> Select<T, TDest>(this IObservableAsync<T> @this, Func<T, CancellationToken, ValueTask<TDest>> selector)
2. public static IObservableAsync<TDest> Select<T, TDest>(this IObservableAsync<T> @this, Func<T, TDest> selector)

1. Overload¶

public static IObservableAsync<TDest> Select<T, TDest>(this IObservableAsync<T> @this, Func<T, CancellationToken, ValueTask<TDest>> selector)

View source

Summary: Projects each element of the observable sequence into a new form using the specified asynchronous selector function.

Type parameters

Name	Description
`T`	The type of the elements in the source sequence.
`TDest`	The type of the value returned by the selector function and produced by the resulting observable sequence.

Parameters

Name	Type	Description
`this`	[IObservableAsync](#	The source observable sequence.
`selector`	Func>	A function that transforms each element of the source sequence into a value of type `TDest` asynchronously. The function receives the source element and a cancellation token.

Returns: IObservableAsync -- An observable sequence of type TDest containing the results of applying the selector function to each element of the source sequence.

Remarks

The selector function is invoked for each element as it is observed. If the selector function throws an exception or returns a faulted task, the error is propagated to the observer. The operation supports cancellation via the provided cancellation token.

2. Overload¶

public static IObservableAsync<TDest> Select<T, TDest>(this IObservableAsync<T> @this, Func<T, TDest> selector)

View source

Summary: Projects each element of the observable sequence into a new form using the specified selector function.

Type parameters

Name	Description
`T`	The type of the elements in the source sequence.
`TDest`	The type of the value returned by the selector function.

Parameters

Name	Type	Description
`this`	[IObservableAsync](#	The source observable sequence.
`selector`	Func	A function that transforms each element of the source sequence into a new value. Cannot be null.

Returns: IObservableAsync -- An observable sequence whose elements are the result of invoking the selector function on each element of the source sequence.

Remarks

The selector function is applied to each element as it is observed. If the selector throws an exception, the error is propagated to the observer. This method does not modify the source sequence; it produces a new sequence with transformed elements.