AsyncEnumerable.MinByAsync Method
Definition
Important
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Overloads
MinByAsync<TSource,TKey>(IAsyncEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>, CancellationToken) |
Returns the minimum value in a generic sequence according to a specified key selector function. |
MinByAsync<TSource,TKey>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask<TKey>>, IComparer<TKey>, CancellationToken) |
Returns the minimum value in a generic sequence according to a specified key selector function. |
MinByAsync<TSource,TKey>(IAsyncEnumerable<TSource>, Func<TSource,TKey>, IComparer<TKey>, CancellationToken)
- Source:
- MinByAsync.cs
Returns the minimum value in a generic sequence according to a specified key selector function.
public static System.Threading.Tasks.ValueTask<TSource?> MinByAsync<TSource,TKey>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);
static member MinByAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, 'Key> * System.Collections.Generic.IComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<'Source>
<Extension()>
Public Function MinByAsync(Of TSource, TKey) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), Optional comparer As IComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of TSource)
Type Parameters
- TSource
The type of the elements of source
.
- TKey
The type of key to compare elements by.
Parameters
- source
- IAsyncEnumerable<TSource>
A sequence of values to determine the minimum value of.
- keySelector
- Func<TSource,TKey>
A function to extract the key for each element.
- comparer
- IComparer<TKey>
The IComparer<T> to compare keys.
- cancellationToken
- CancellationToken
The CancellationToken to monitor for cancellation requests. The default is None.
Returns
The value with the minimum key in the sequence.
Exceptions
source
is null
.
No key extracted from source
implements the IComparable or IComparable<T> interface.
Remarks
If TKey
is a reference type and the source sequence is empty or contains only values that are null
, this method returns null
.
Applies to
MinByAsync<TSource,TKey>(IAsyncEnumerable<TSource>, Func<TSource,CancellationToken,ValueTask<TKey>>, IComparer<TKey>, CancellationToken)
- Source:
- MinByAsync.cs
Returns the minimum value in a generic sequence according to a specified key selector function.
public static System.Threading.Tasks.ValueTask<TSource?> MinByAsync<TSource,TKey>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<TKey>> keySelector, System.Collections.Generic.IComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);
static member MinByAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<'Key>> * System.Collections.Generic.IComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<'Source>
<Extension()>
Public Function MinByAsync(Of TSource, TKey) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, CancellationToken, ValueTask(Of TKey)), Optional comparer As IComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of TSource)
Type Parameters
- TSource
The type of the elements of source
.
- TKey
The type of key to compare elements by.
Parameters
- source
- IAsyncEnumerable<TSource>
A sequence of values to determine the minimum value of.
- keySelector
- Func<TSource,CancellationToken,ValueTask<TKey>>
A function to extract the key for each element.
- comparer
- IComparer<TKey>
The IComparer<T> to compare keys.
- cancellationToken
- CancellationToken
The CancellationToken to monitor for cancellation requests. The default is None.
Returns
The value with the minimum key in the sequence.
Exceptions
source
is null
.
No key extracted from source
implements the IComparable or IComparable<T> interface.
Remarks
If TKey
is a reference type and the source sequence is empty or contains only values that are null
, this method returns null
.