Enumerable.AggregateBy 方法

定義

命名空間:

System.Linq

組件:

System.Linq.dll

多載

AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, Func<TKey,TAccumulate>, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)
AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)

AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, Func<TKey,TAccumulate>, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)

來源:

AggregateBy.cs

public static System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TAccumulate>> AggregateBy<TSource,TKey,TAccumulate> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, Func<TKey,TAccumulate> seedSelector, Func<TAccumulate,TSource,TAccumulate> func, System.Collections.Generic.IEqualityComparer<TKey>? keyComparer = default);

static member AggregateBy : seq<'Source> * Func<'Source, 'Key> * Func<'Key, 'Accumulate> * Func<'Accumulate, 'Source, 'Accumulate> * System.Collections.Generic.IEqualityComparer<'Key> -> seq<System.Collections.Generic.KeyValuePair<'Key, 'Accumulate>>

<Extension()>
Public Function AggregateBy(Of TSource, TKey, TAccumulate) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), seedSelector As Func(Of TKey, TAccumulate), func As Func(Of TAccumulate, TSource, TAccumulate), Optional keyComparer As IEqualityComparer(Of TKey) = Nothing) As IEnumerable(Of KeyValuePair(Of TKey, TAccumulate))

類型參數

TSource

TKey

TAccumulate

參數

source

IEnumerable<TSource>

keySelector

Func<TSource,TKey>

seedSelector

Func<TKey,TAccumulate>

func

Func<TAccumulate,TSource,TAccumulate>

keyComparer

IEqualityComparer<TKey>

傳回

IEnumerable<KeyValuePair<TKey,TAccumulate>>

AggregateBy<TSource,TKey,TAccumulate>(IEnumerable<TSource>, Func<TSource, TKey>, TAccumulate, Func<TAccumulate,TSource,TAccumulate>, IEqualityComparer<TKey>)

來源:

AggregateBy.cs

public static System.Collections.Generic.IEnumerable<System.Collections.Generic.KeyValuePair<TKey,TAccumulate>> AggregateBy<TSource,TKey,TAccumulate> (this System.Collections.Generic.IEnumerable<TSource> source, Func<TSource,TKey> keySelector, TAccumulate seed, Func<TAccumulate,TSource,TAccumulate> func, System.Collections.Generic.IEqualityComparer<TKey>? keyComparer = default);

static member AggregateBy : seq<'Source> * Func<'Source, 'Key> * 'Accumulate * Func<'Accumulate, 'Source, 'Accumulate> * System.Collections.Generic.IEqualityComparer<'Key> -> seq<System.Collections.Generic.KeyValuePair<'Key, 'Accumulate>>

<Extension()>
Public Function AggregateBy(Of TSource, TKey, TAccumulate) (source As IEnumerable(Of TSource), keySelector As Func(Of TSource, TKey), seed As TAccumulate, func As Func(Of TAccumulate, TSource, TAccumulate), Optional keyComparer As IEqualityComparer(Of TKey) = Nothing) As IEnumerable(Of KeyValuePair(Of TKey, TAccumulate))

類型參數

TSource

TKey

TAccumulate

參數

source

IEnumerable<TSource>

keySelector

Func<TSource,TKey>

seed

TAccumulate

func

Func<TAccumulate,TSource,TAccumulate>

keyComparer

IEqualityComparer<TKey>

傳回

IEnumerable<KeyValuePair<TKey,TAccumulate>>