Method GroupAdjacent

GroupAdjacent<TSource, TKey>(IAsyncEnumerable<TSource>, Func<TSource, TKey>)

Groups the adjacent elements of a sequence according to a specified key selector function.

Declaration

public static IAsyncEnumerable<IGrouping<TKey, TSource>> GroupAdjacent<TSource, TKey>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.

Returns

Type	Description
IAsyncEnumerable<IGrouping<TKey, TSource>>	A sequence of groupings where each grouping (IGrouping<TKey, TElement>) contains the key and the adjacent elements in the same order as found in the source sequence.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.

GroupAdjacent<TSource, TKey>(IAsyncEnumerable<TSource>, Func<TSource, TKey>, IEqualityComparer<TKey>?)

Groups the adjacent elements of a sequence according to a specified key selector function and compares the keys by using a specified comparer.

Declaration

public static IAsyncEnumerable<IGrouping<TKey, TSource>> GroupAdjacent<TSource, TKey>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector, IEqualityComparer<TKey>? comparer)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.
IEqualityComparer<TKey>	comparer	An IEqualityComparer<T> to compare keys.

Returns

Type	Description
IAsyncEnumerable<IGrouping<TKey, TSource>>	A sequence of groupings where each grouping (IGrouping<TKey, TElement>) contains the key and the adjacent elements in the same order as found in the source sequence.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.

GroupAdjacent<TSource, TKey, TElement>(IAsyncEnumerable<TSource>, Func<TSource, TKey>, Func<TSource, TElement>)

Groups the adjacent elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function.

Declaration

public static IAsyncEnumerable<IGrouping<TKey, TElement>> GroupAdjacent<TSource, TKey, TElement>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.
Func<TSource, TElement>	elementSelector	A function to map each source element to an element in the resulting grouping.

Returns

Type	Description
IAsyncEnumerable<IGrouping<TKey, TElement>>	A sequence of groupings where each grouping (IGrouping<TKey, TElement>) contains the key and the adjacent elements (of type TElement) in the same order as found in the source sequence.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.
TElement	The type of the elements in the resulting groupings.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.
ArgumentNullException	elementSelector is null.

GroupAdjacent<TSource, TKey, TElement>(IAsyncEnumerable<TSource>, Func<TSource, TKey>, Func<TSource, TElement>, IEqualityComparer<TKey>?)

Groups the adjacent elements of a sequence according to a specified key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

Declaration

public static IAsyncEnumerable<IGrouping<TKey, TElement>> GroupAdjacent<TSource, TKey, TElement>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TSource, TElement> elementSelector, IEqualityComparer<TKey>? comparer)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.
Func<TSource, TElement>	elementSelector	A function to map each source element to an element in the resulting grouping.
IEqualityComparer<TKey>	comparer	An IEqualityComparer<T> to compare keys.

Returns

Type	Description
IAsyncEnumerable<IGrouping<TKey, TElement>>	A sequence of groupings where each grouping (IGrouping<TKey, TElement>) contains the key and the adjacent elements (of type TElement) in the same order as found in the source sequence.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.
TElement	The type of the elements in the resulting groupings.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.
ArgumentNullException	elementSelector is null.

GroupAdjacent<TSource, TKey, TResult>(IAsyncEnumerable<TSource>, Func<TSource, TKey>, Func<TKey, IReadOnlyList<TSource>, TResult>)

Groups the adjacent elements of a sequence according to a specified key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

Declaration

public static IAsyncEnumerable<TResult> GroupAdjacent<TSource, TKey, TResult>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TKey, IReadOnlyList<TSource>, TResult> resultSelector)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.
Func<TKey, IReadOnlyList<TSource>, TResult>	resultSelector	A function to map each key and associated source elements to a result object.

Returns

Type	Description
IAsyncEnumerable<TResult>	A collection of elements of type TResult where each element represents a projection over a group and its key.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.
TResult	The type of the elements in the resulting sequence.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.
ArgumentNullException	resultSelector is null.

GroupAdjacent<TSource, TKey, TResult>(IAsyncEnumerable<TSource>, Func<TSource, TKey>, Func<TKey, IReadOnlyList<TSource>, TResult>, IEqualityComparer<TKey>?)

Groups the adjacent elements of a sequence according to a specified key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.

Declaration

public static IAsyncEnumerable<TResult> GroupAdjacent<TSource, TKey, TResult>(this IAsyncEnumerable<TSource> source, Func<TSource, TKey> keySelector, Func<TKey, IReadOnlyList<TSource>, TResult> resultSelector, IEqualityComparer<TKey>? comparer)

Parameters

Type	Name	Description
IAsyncEnumerable<TSource>	source	A sequence whose elements to group.
Func<TSource, TKey>	keySelector	A function to extract the key for each element.
Func<TKey, IReadOnlyList<TSource>, TResult>	resultSelector	A function to map each key and associated source elements to a result object.
IEqualityComparer<TKey>	comparer	An IEqualityComparer<T> to compare keys.

Returns

Type	Description
IAsyncEnumerable<TResult>	A collection of elements of type TResult where each element represents a projection over a group and its key.

Type Parameters

Name	Description
TSource	The type of the elements of source.
TKey	The type of the key returned by keySelector.
TResult	The type of the elements in the resulting sequence.

Remarks

This method is implemented by using deferred execution and streams the groupings. The grouping elements, however, are buffered. Each grouping is therefore yielded as soon as it is complete and before the next grouping occurs.

Exceptions

Type	Condition
ArgumentNullException	source is null.
ArgumentNullException	keySelector is null.
ArgumentNullException	resultSelector is null.