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SingleAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,Boolean>, CancellationToken) |
Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists. |
SingleAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask<Boolean>>, CancellationToken) |
Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists. |
SingleAsync<TSource>(IAsyncEnumerable<TSource>, CancellationToken) |
Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence. |
Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.
public static System.Threading.Tasks.ValueTask<TSource> SingleAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,bool> predicate, System.Threading.CancellationToken cancellationToken = default);
static member SingleAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, bool> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<'Source>
<Extension()>
Public Function SingleAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), predicate As Func(Of TSource, Boolean), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of TSource)
The type of the elements of source.
An IAsyncEnumerable<T> to return the single element of.
The CancellationToken to monitor for cancellation requests. The default is None.
The single element of the input sequence that satisfies a condition.
predicate
is null
.
More than one element satisfies the condition in predicate
(via the returned task).
Product | Versions |
---|---|
.NET | 8 (package-provided), 9 (package-provided), 10 (package-provided), 10 |
.NET Framework | 4.6.2 (package-provided), 4.7 (package-provided), 4.7.1 (package-provided), 4.7.2 (package-provided), 4.8 (package-provided) |
.NET Standard | 2.0 (package-provided) |
Returns the only element of a sequence that satisfies a specified condition, and throws an exception if more than one such element exists.
public static System.Threading.Tasks.ValueTask<TSource> SingleAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<bool>> predicate, System.Threading.CancellationToken cancellationToken = default);
static member SingleAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<bool>> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<'Source>
<Extension()>
Public Function SingleAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), predicate As Func(Of TSource, CancellationToken, ValueTask(Of Boolean)), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of TSource)
The type of the elements of source.
An IAsyncEnumerable<T> to return the single element of.
A function to test an element for a condition.
The CancellationToken to monitor for cancellation requests. The default is None.
The single element of the input sequence that satisfies a condition.
predicate
is null
.
More than one element satisfies the condition in predicate
(via the returned task).
Product | Versions |
---|---|
.NET | 8 (package-provided), 9 (package-provided), 10 (package-provided), 10 |
.NET Framework | 4.6.2 (package-provided), 4.7 (package-provided), 4.7.1 (package-provided), 4.7.2 (package-provided), 4.8 (package-provided) |
.NET Standard | 2.0 (package-provided) |
Returns the only element of a sequence, and throws an exception if there is not exactly one element in the sequence.
public static System.Threading.Tasks.ValueTask<TSource> SingleAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Threading.CancellationToken cancellationToken = default);
static member SingleAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<'Source>
<Extension()>
Public Function SingleAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of TSource)
The type of the elements of source.
An IAsyncEnumerable<T> to return the single element of.
The CancellationToken to monitor for cancellation requests. The default is None.
The single element of the input sequence.
source
is null
.
The source
sequence contains more than one element. (via the returned task).
Product | Versions |
---|---|
.NET | 8 (package-provided), 9 (package-provided), 10 (package-provided), 10 |
.NET Framework | 4.6.2 (package-provided), 4.7 (package-provided), 4.7.1 (package-provided), 4.7.2 (package-provided), 4.8 (package-provided) |
.NET Standard | 2.0 (package-provided) |
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