Enumerable.AggregateBy 方法

定义

命名空间:

System.Linq

程序集:

System.Linq.dll

重载

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>)

Source:

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))

类型参数

TSource

TKey

TAccumulate

参数

source

IEnumerable<TSource>

keySelector

Func<TSource,TKey>

seedSelector

Func<TKey,TAccumulate>

func

Func<TAccumulate,TSource,TAccumulate>

keyComparer

IEqualityComparer<TKey>

返回

IEnumerable<KeyValuePair<TKey,TAccumulate>>

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

Source:

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))

类型参数

TSource

TKey

TAccumulate

参数

source

IEnumerable<TSource>

keySelector

Func<TSource,TKey>

seed

TAccumulate

func

Func<TAccumulate,TSource,TAccumulate>

keyComparer

IEqualityComparer<TKey>

返回

IEnumerable<KeyValuePair<TKey,TAccumulate>>