AsyncEnumerable.ToLookupAsync Method (System.Linq) (original) (raw)
Definition
Namespace:
Assembly:
System.Linq.AsyncEnumerable.dll
Package:
System.Linq.AsyncEnumerable v10.0.0-preview.5.25277.114
Important
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Overloads
ToLookupAsync<TSource,TKey,TElement>(IAsyncEnumerable, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer, CancellationToken)
Source:
Source:
public static System.Threading.Tasks.ValueTask<System.Linq.ILookup<TKey,TElement>> ToLookupAsync<TSource,TKey,TElement>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);static member ToLookupAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> * System.Collections.Generic.IEqualityComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<System.Linq.ILookup<'Key, 'Element>><Extension()>
Public Function ToLookupAsync(Of TSource, TKey, TElement) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement), Optional comparer As IEqualityComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of ILookup(Of TKey, TElement))Type Parameters
TSource
The type of the elements of source.
TKey
The type of the key returned by keySelector.
TElement
The type of the value returned by elementSelector.
Parameters
keySelector
Func<TSource,TKey>
A function to extract a key from each element.
elementSelector
Func<TSource,TElement>
A transform function to produce a result element value from each element.
Returns
A ILookup<TKey,TElement> that contains keys and values.
Exceptions
Applies to
ToLookupAsync<TSource,TKey,TElement>(IAsyncEnumerable, Func<TSource,CancellationToken,ValueTask>, Func<TSource, CancellationToken,ValueTask>, IEqualityComparer, CancellationToken)
Source:
Source:
public static System.Threading.Tasks.ValueTask<System.Linq.ILookup<TKey,TElement>> ToLookupAsync<TSource,TKey,TElement>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<TKey>> keySelector, Func<TSource,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<TElement>> elementSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);static member ToLookupAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<'Key>> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<'Element>> * System.Collections.Generic.IEqualityComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<System.Linq.ILookup<'Key, 'Element>><Extension()>
Public Function ToLookupAsync(Of TSource, TKey, TElement) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, CancellationToken, ValueTask(Of TKey)), elementSelector As Func(Of TSource, CancellationToken, ValueTask(Of TElement)), Optional comparer As IEqualityComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of ILookup(Of TKey, TElement))Type Parameters
TSource
The type of the elements of source.
TKey
The type of the key returned by keySelector.
TElement
The type of the value returned by elementSelector.
Parameters
Returns
A ILookup<TKey,TElement> that contains keys and values.
Exceptions
Applies to
ToLookupAsync<TSource,TKey>(IAsyncEnumerable, Func<TSource,CancellationToken,ValueTask>, IEqualityComparer, CancellationToken)
Source:
Source:
public static System.Threading.Tasks.ValueTask<System.Linq.ILookup<TKey,TSource>> ToLookupAsync<TSource,TKey>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,System.Threading.CancellationToken,System.Threading.Tasks.ValueTask<TKey>> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);static member ToLookupAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, System.Threading.CancellationToken, System.Threading.Tasks.ValueTask<'Key>> * System.Collections.Generic.IEqualityComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<System.Linq.ILookup<'Key, 'Source>><Extension()>
Public Function ToLookupAsync(Of TSource, TKey) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, CancellationToken, ValueTask(Of TKey)), Optional comparer As IEqualityComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of ILookup(Of TKey, TSource))Type Parameters
TSource
The type of the elements of source.
TKey
The type of the key returned by keySelector.
Parameters
Returns
A ILookup<TKey,TElement> that contains keys and values.
Exceptions
Applies to
ToLookupAsync<TSource,TKey>(IAsyncEnumerable, Func<TSource,TKey>, IEqualityComparer, CancellationToken)
Source:
Source:
public static System.Threading.Tasks.ValueTask<System.Linq.ILookup<TKey,TSource>> ToLookupAsync<TSource,TKey>(this System.Collections.Generic.IAsyncEnumerable<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer = default, System.Threading.CancellationToken cancellationToken = default);static member ToLookupAsync : System.Collections.Generic.IAsyncEnumerable<'Source> * Func<'Source, 'Key> * System.Collections.Generic.IEqualityComparer<'Key> * System.Threading.CancellationToken -> System.Threading.Tasks.ValueTask<System.Linq.ILookup<'Key, 'Source>><Extension()>
Public Function ToLookupAsync(Of TSource, TKey) (source As IAsyncEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), Optional comparer As IEqualityComparer(Of TKey) = Nothing, Optional cancellationToken As CancellationToken = Nothing) As ValueTask(Of ILookup(Of TKey, TSource))Type Parameters
TSource
The type of the elements of source.
TKey
The type of the key returned by keySelector.
Parameters
keySelector
Func<TSource,TKey>
A function to extract a key from each element.
Returns
A ILookup<TKey,TElement> that contains keys and values.