ParallelEnumerable.GroupBy Method

Definition

Namespace:: System.Linq

Assemblies:: System.Core.dll, System.Linq.Parallel.dll

Assemblies:: netstandard.dll, System.Linq.Parallel.dll

Assembly:: System.Linq.Parallel.dll

Assembly:: System.Core.dll

Assembly:: netstandard.dll

Important

Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.

Groups in parallel the elements of a sequence according to a key selector function.

Overloads

GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)	Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function.
GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>,TResult>)	Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function.
GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)	Groups in parallel the elements of a sequence according to a specified key selector function and projects the elements for each group by using a specified function.
GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)	Groups in parallel the elements of a sequence according to a key selector function. The keys are compared by using a comparer and each group's elements are projected by using a specified function.
GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>)	Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.
GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>, IEqualityComparer<TKey>)	Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The keys are compared by using a specified comparer.
GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)	Groups in parallel the elements of a sequence according to a specified key selector function and compares the keys by using a specified IComparer<T>.
GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>)	Groups in parallel the elements of a sequence according to a specified key-selector function.

GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. Key values are compared by using a specified comparer, and the elements of each group are projected by using a specified function.

public:
generic <typename TSource, typename TKey, typename TElement, typename TResult>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<TResult> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector, Func<TKey, System::Collections::Generic::IEnumerable<TElement> ^, TResult> ^ resultSelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TElement,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, Func<TKey,System.Collections.Generic.IEnumerable<TElement>,TResult> resultSelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TElement,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, Func<TKey,System.Collections.Generic.IEnumerable<TElement>,TResult> resultSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> * Func<'Key, seq<'Element>, 'Result> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Linq.ParallelQuery<'Result>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TElement, TResult) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement), resultSelector As Func(Of TKey, IEnumerable(Of TElement), TResult), comparer As IEqualityComparer(Of TKey)) As ParallelQuery(Of TResult)

Type Parameters

TSource

The type of the elements of source.

TKey

The type of the key returned by keySelector.

TElement

The type of the elements in each IGrouping{TKey, TElement}.

TResult

The type of the result value returned by resultSelector.

Parameters

source: ParallelQuery<TSource>

A sequence whose elements to group.

keySelector: Func<TSource,TKey>

A function to extract the key for each element.

elementSelector: Func<TSource,TElement>

A function to map each source element to an element in an IGrouping{Key, TElement}.

resultSelector: Func<TKey,IEnumerable<TElement>,TResult>

A function to create a result value from each group.

comparer: IEqualityComparer<TKey>

An IEqualityComparer<T> to compare keys.

Returns

ParallelQuery<TResult>

A sequence of elements of type TResult where each element represents a projection over a group and its key.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or keySelector or elementSelector or resultSelector is null (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>,TResult>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The elements of each group are projected by using a specified function.

public:
generic <typename TSource, typename TKey, typename TElement, typename TResult>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<TResult> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector, Func<TKey, System::Collections::Generic::IEnumerable<TElement> ^, TResult> ^ resultSelector);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TElement,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, Func<TKey,System.Collections.Generic.IEnumerable<TElement>,TResult> resultSelector);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> * Func<'Key, seq<'Element>, 'Result> -> System.Linq.ParallelQuery<'Result>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TElement, TResult) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement), resultSelector As Func(Of TKey, IEnumerable(Of TElement), TResult)) As ParallelQuery(Of TResult)

Type Parameters

TSource

The type of the elements of source.

TKey

The type of the key returned by keySelector.

TElement

The type of the elements in each IGrouping{TKey, TElement}.

TResult

The type of the result value returned by resultSelector.

Parameters

source: ParallelQuery<TSource>

A sequence whose elements to group.

keySelector: Func<TSource,TKey>

A function to extract the key for each element.

elementSelector: Func<TSource,TElement>

A function to map each source element to an element in an IGrouping<TKey, TElement>.

resultSelector: Func<TKey,IEnumerable<TElement>,TResult>

A function to create a result value from each group.

Returns

ParallelQuery<TResult>

A sequence of elements of type TResult where each element represents a projection over a group and its key.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or keySelector or elementSelector or resultSelector is null (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

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

public:
generic <typename TSource, typename TKey, typename TElement>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<System::Linq::IGrouping<TKey, TElement> ^> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TElement>> GroupBy<TSource,TKey,TElement>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> -> System.Linq.ParallelQuery<System.Linq.IGrouping<'Key, 'Element>>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TElement) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement)) As ParallelQuery(Of IGrouping(Of TKey, TElement))

Type Parameters

TSource

The type of elements of source.

TKey

The type of the key returned by keySelector.

TElement

The type of the elements in the IGrouping<TKey,TElement>.

Parameters

source: ParallelQuery<TSource>

An OrderedParallelQuery<TSource> that contains elements to sort.

keySelector: Func<TSource,TKey>

A function to extract a key from an element.

elementSelector: Func<TSource,TElement>

A function to map each source element to an element in an IGrouping<TKey,TElement>.

Returns

ParallelQuery<IGrouping<TKey,TElement>>

A sequence of groups that are sorted descending according to TKey.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or elementSelector is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

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

public:
generic <typename TSource, typename TKey, typename TElement>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<System::Linq::IGrouping<TKey, TElement> ^> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TSource, TElement> ^ elementSelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TElement>> GroupBy<TSource,TKey,TElement>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TElement>> GroupBy<TSource,TKey,TElement>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TSource,TElement> elementSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Source, 'Element> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Linq.ParallelQuery<System.Linq.IGrouping<'Key, 'Element>>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TElement) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), elementSelector As Func(Of TSource, TElement), comparer As IEqualityComparer(Of TKey)) As ParallelQuery(Of IGrouping(Of TKey, TElement))

Type Parameters

TSource

The type of elements of source.

TKey

The type of the key returned by keySelector.

TElement

The type of the elements in the IGrouping.

Parameters

source: ParallelQuery<TSource>

An OrderedParallelQuery{TSource}that contains elements to sort.

keySelector: Func<TSource,TKey>

A function to extract a key from an element.

elementSelector: Func<TSource,TElement>

A function to map each source element to an element in an IGrouping.

comparer: IEqualityComparer<TKey>

An IComparer{TSource} to compare keys.

Returns

ParallelQuery<IGrouping<TKey,TElement>>

A sequence of groups that are sorted descending according to TKey.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or elementSelector is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key.

public:
generic <typename TSource, typename TKey, typename TResult>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<TResult> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TKey, System::Collections::Generic::IEnumerable<TSource> ^, TResult> ^ resultSelector);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TKey,System.Collections.Generic.IEnumerable<TSource>,TResult> resultSelector);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Key, seq<'Source>, 'Result> -> System.Linq.ParallelQuery<'Result>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TResult) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), resultSelector As Func(Of TKey, IEnumerable(Of TSource), TResult)) As ParallelQuery(Of TResult)

Type Parameters

TSource

The type of the elements of source.

TKey

The type of the key returned by keySelector.

TResult

The type of the result value returned by resultSelector.

Parameters

source: ParallelQuery<TSource>

A sequence whose elements to group.

keySelector: Func<TSource,TKey>

A function to extract the key for each element.

resultSelector: Func<TKey,IEnumerable<TSource>,TResult>

A function to create a result value from each group.

Returns

ParallelQuery<TResult>

A sequence of elements of type TResult where each element represents a projection over a group and its key.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or resultSelector is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>, IEqualityComparer<TKey>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups in parallel the elements of a sequence according to a specified key selector function and creates a result value from each group and its key. The keys are compared by using a specified comparer.

public:
generic <typename TSource, typename TKey, typename TResult>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<TResult> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, Func<TKey, System::Collections::Generic::IEnumerable<TSource> ^, TResult> ^ resultSelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TKey,System.Collections.Generic.IEnumerable<TSource>,TResult> resultSelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);

public static System.Linq.ParallelQuery<TResult> GroupBy<TSource,TKey,TResult>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, Func<TKey,System.Collections.Generic.IEnumerable<TSource>,TResult> resultSelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * Func<'Key, seq<'Source>, 'Result> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Linq.ParallelQuery<'Result>

<Extension()>
Public Function GroupBy(Of TSource, TKey, TResult) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), resultSelector As Func(Of TKey, IEnumerable(Of TSource), TResult), comparer As IEqualityComparer(Of TKey)) As ParallelQuery(Of TResult)

Type Parameters

TSource

The type of the elements of source.

TKey

The type of the key returned by keySelector.

TResult

The type of the result value returned by resultSelector.

Parameters

source: ParallelQuery<TSource>

A sequence whose elements to group.

keySelector: Func<TSource,TKey>

A function to extract the key for each element.

resultSelector: Func<TKey,IEnumerable<TSource>,TResult>

A function to create a result value from each group.

comparer: IEqualityComparer<TKey>

An IEqualityComparer<T> to compare keys.

Returns

ParallelQuery<TResult>

A sequence of groups.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or resultSelector is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups in parallel the elements of a sequence according to a specified key selector function and compares the keys by using a specified IComparer<T>.

public:
generic <typename TSource, typename TKey>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<System::Linq::IGrouping<TKey, TSource> ^> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector, System::Collections::Generic::IEqualityComparer<TKey> ^ comparer);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TSource>> GroupBy<TSource,TKey>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey> comparer);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TSource>> GroupBy<TSource,TKey>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector, System.Collections.Generic.IEqualityComparer<TKey>? comparer);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> * System.Collections.Generic.IEqualityComparer<'Key> -> System.Linq.ParallelQuery<System.Linq.IGrouping<'Key, 'Source>>

<Extension()>
Public Function GroupBy(Of TSource, TKey) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey), comparer As IEqualityComparer(Of TKey)) As ParallelQuery(Of IGrouping(Of TKey, TSource))

Type Parameters

TSource

The type of elements of source.

TKey

The type of the key returned by keySelector.

Parameters

source: ParallelQuery<TSource>

An OrderedParallelQuery<TSource> that contains elements to sort.

keySelector: Func<TSource,TKey>

A function to extract a key from an element.

comparer: IEqualityComparer<TKey>

An IComparer<T> to compare keys.

Returns

ParallelQuery<IGrouping<TKey,TSource>>

A sequence of groups that are sorted descending according to TKey.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>)

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Source:: ParallelEnumerable.cs

Groups in parallel the elements of a sequence according to a specified key-selector function.

public:
generic <typename TSource, typename TKey>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::ParallelQuery<System::Linq::IGrouping<TKey, TSource> ^> ^ GroupBy(System::Linq::ParallelQuery<TSource> ^ source, Func<TSource, TKey> ^ keySelector);

public static System.Linq.ParallelQuery<System.Linq.IGrouping<TKey,TSource>> GroupBy<TSource,TKey>(this System.Linq.ParallelQuery<TSource> source, Func<TSource,TKey> keySelector);

static member GroupBy : System.Linq.ParallelQuery<'Source> * Func<'Source, 'Key> -> System.Linq.ParallelQuery<System.Linq.IGrouping<'Key, 'Source>>

<Extension()>
Public Function GroupBy(Of TSource, TKey) (source As ParallelQuery(Of TSource), keySelector As Func(Of TSource, TKey)) As ParallelQuery(Of IGrouping(Of TKey, TSource))

Type Parameters

TSource

The type of elements of source.

TKey

The type of the key returned by keySelector.

Parameters

source: ParallelQuery<TSource>

An OrderedParallelQuery<TSource> that contains elements to sort.

keySelector: Func<TSource,TKey>

A function to extract a key from an element.

Returns

ParallelQuery<IGrouping<TKey,TSource>>

A sequence of groups that are sorted in descending order according to TKey.

Exceptions

OperationCanceledException

The query was canceled with the token passed in through WithCancellation<TSource>(ParallelQuery<TSource>, CancellationToken).

ArgumentNullException

source or keySelector is a null reference (Nothing in Visual Basic).

AggregateException

One or more exceptions occurred during the evaluation of the query.

Applies to

.NET 10 and other versions

Product	Versions
.NET	Core 1.0, Core 1.1, Core 2.0, Core 2.1, Core 2.2, Core 3.0, Core 3.1, 5, 6, 7, 8, 9, 10
.NET Framework	4.0, 4.5, 4.5.1, 4.5.2, 4.6, 4.6.1, 4.6.2, 4.7, 4.7.1, 4.7.2, 4.8, 4.8.1
.NET Standard	2.0, 2.1
UWP	10.0

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ParallelEnumerable.GroupBy Method

Definition

Overloads

GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>, TResult>, IEqualityComparer<TKey>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey,TElement,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, Func<TKey,IEnumerable<TElement>,TResult>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey,TElement>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TSource,TElement>, IEqualityComparer<TKey>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey,TResult>(ParallelQuery<TSource>, Func<TSource,TKey>, Func<TKey,IEnumerable<TSource>,TResult>, IEqualityComparer<TKey>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>, IEqualityComparer<TKey>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

GroupBy<TSource,TKey>(ParallelQuery<TSource>, Func<TSource,TKey>)

Type Parameters

Parameters

Returns

Exceptions

See also

Applies to

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