AsyncEnumerable.CountAsync Method
Definition
Important
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Overloads
| CountAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,Boolean>, CancellationToken) |
Returns the number of elements in a sequence satisfy a condition. |
| CountAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask<Boolean>>, CancellationToken) |
Returns the number of elements in a sequence satisfy a condition. |
| CountAsync<TSource>(IAsyncEnumerable<TSource>, CancellationToken) |
Returns the number of elements in a sequence. |
CountAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,Boolean>, CancellationToken)
- Source:
- CountAsync.cs
Returns the number of elements in a sequence satisfy a condition.
public static System.Threading.Tasks.ValueTask<int> CountAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,bool> predicate, System.Threading.CancellationToken cancellationToken = default);static member CountAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, bool> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<int><Extension()>
Public Function CountAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), predicate As Func(Of TSource, Boolean), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of Integer)Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- IAsyncEnumerable<TSource>
A sequence that contains elements to be tested and counted.
- cancellationToken
- CancellationToken
The CancellationToken to monitor for cancellation requests. The default is None.
Returns
The number of elements in the input sequence that satisfy the condition in the predicate function.
Exceptions
source is null.
The number of elements that satisfy the condition is larger than MaxValue (via the returned task).
Applies to
CountAsync<TSource>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask<Boolean>>, CancellationToken)
- Source:
- CountAsync.cs
Returns the number of elements in a sequence satisfy a condition.
public static System.Threading.Tasks.ValueTask<int> CountAsync<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 CountAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<bool>> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<int><Extension()>
Public Function CountAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), predicate As Func(Of TSource, CancellationToken, ValueTask(Of Boolean)), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of Integer)Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- IAsyncEnumerable<TSource>
A sequence that contains elements to be tested and counted.
- predicate
- Func<TSource,CancellationToken,ValueTask<Boolean>>
A function to test each element for a condition.
- cancellationToken
- CancellationToken
The CancellationToken to monitor for cancellation requests. The default is None.
Returns
The number of elements in the input sequence that satisfy the condition in the predicate function.
Exceptions
source is null.
The number of elements that satisfy the condition is larger than MaxValue (via the returned task).
Applies to
CountAsync<TSource>(IAsyncEnumerable<TSource>, CancellationToken)
- Source:
- CountAsync.cs
Returns the number of elements in a sequence.
public static System.Threading.Tasks.ValueTask<int> CountAsync<TSource>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, System.Threading.CancellationToken cancellationToken = default);static member CountAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<int><Extension()>
Public Function CountAsync(Of TSource) (source As IAsyncEnumerable(Of TSource), Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of Integer)Type Parameters
- TSource
The type of the elements of source.
Parameters
- source
- IAsyncEnumerable<TSource>
A sequence that contains elements to be counted.
- cancellationToken
- CancellationToken
The CancellationToken to monitor for cancellation requests. The default is None.
Returns
The number of elements in the input sequence.
Exceptions
source is null.
The number of elements in source is larger than MaxValue (via the returned task).
