Queryable.AggregateBy 方法

定義

命名空間:

System.Linq

組件:

System.Linq.Queryable.dll

多載

AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TKey,TAccumulate>>, Expression<Func<TAccumulate, TSource,TAccumulate>>, IEqualityComparer<TKey>)
AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, TAccumulate, Expression<Func<TAccumulate,TSource,TAccumulate>>, IEqualityComparer<TKey>)

AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TKey,TAccumulate>>, Expression<Func<TAccumulate, TSource,TAccumulate>>, IEqualityComparer<TKey>)

來源:

Queryable.cs

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

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

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

類型參數

TSource

TKey

TAccumulate

參數

source

IQueryable<TSource>

keySelector

Expression<Func<TSource,TKey>>

seedSelector

Expression<Func<TKey,TAccumulate>>

func

Expression<Func<TAccumulate,TSource,TAccumulate>>

keyComparer

IEqualityComparer<TKey>

傳回

IQueryable<KeyValuePair<TKey,TAccumulate>>

AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, TAccumulate, Expression<Func<TAccumulate,TSource,TAccumulate>>, IEqualityComparer<TKey>)

來源:

Queryable.cs

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

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

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

類型參數

TSource

TKey

TAccumulate

參數

source

IQueryable<TSource>

keySelector

Expression<Func<TSource,TKey>>

seed

TAccumulate

func

Expression<Func<TAccumulate,TSource,TAccumulate>>

keyComparer

IEqualityComparer<TKey>

傳回

IQueryable<KeyValuePair<TKey,TAccumulate>>