Queryable.AggregateBy 方法
定义
重要
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重载
AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, Expression<Func<TKey,TAccumulate>>, Expression<Func<TAccumulate, TSource,TAccumulate>>, IEqualityComparer<TKey>)
- Source:
- 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))
类型参数
- TSource
- TKey
- TAccumulate
参数
- source
- IQueryable<TSource>
- keySelector
- Expression<Func<TSource,TKey>>
- seedSelector
- Expression<Func<TKey,TAccumulate>>
- func
- Expression<Func<TAccumulate,TSource,TAccumulate>>
- keyComparer
- IEqualityComparer<TKey>
返回
IQueryable<KeyValuePair<TKey,TAccumulate>>
适用于
AggregateBy<TSource,TKey,TAccumulate>(IQueryable<TSource>, Expression<Func<TSource, TKey>>, TAccumulate, Expression<Func<TAccumulate,TSource,TAccumulate>>, IEqualityComparer<TKey>)
- Source:
- 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))
类型参数
- TSource
- TKey
- TAccumulate
参数
- source
- IQueryable<TSource>
- keySelector
- Expression<Func<TSource,TKey>>
- seed
- TAccumulate
- func
- Expression<Func<TAccumulate,TSource,TAccumulate>>
- keyComparer
- IEqualityComparer<TKey>
返回
IQueryable<KeyValuePair<TKey,TAccumulate>>
适用于
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