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Metodi LINQ supportati e non supportati (LINQ to Entities)

Contenuto della sezione vengono fornite informazioni sugli operatori di query standard LINQ (Language Integrated Query) supportati o non supportati nelle query LINQ to Entities. Numerosi operatori di query standard LINQ dispongono di una versione di overload che accetta un argomento integer. L'argomento integer corrisponde a un indice in base zero nella sequenza che si sta usando, un oggetto IEqualityComparer<T> o un oggetto IComparer<T>. Se non specificato diversamente, queste versioni di overload degli operatori di query standard LINQ non sono supportate e quando si tenta di usarle viene generata un'eccezione.

Metodi di proiezione e di restrizione

La maggior parte dei metodi di proiezione e di restrizione LINQ è supportata nelle query LINQ to Entities, fatta eccezione per i metodi che accettano un argomento posizionale. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di proiezione e di restrizione supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
Select Supportato Function Select(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> Select<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector )
Select Non supportato Function Select(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Integer, TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> Select<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, int, TResult>> selector )
SelectMany Supportato Function SelectMany(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, IEnumerable(Of TResult))) _ ) As IQueryable(Of TResult) IQueryable<TResult> SelectMany<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, IEnumerable<TResult>>> selector )
SelectMany Non supportato Function SelectMany(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Integer, IEnumerable(Of TResult))) _ ) As IQueryable(Of TResult) IQueryable<TResult> SelectMany<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, int, IEnumerable<TResult>>> selector )
SelectMany Supportato Function SelectMany(Of TSource, TCollection, TResult) ( _ source As IQueryable(Of TSource), _ collectionSelector As Expression(Of Func(Of TSource, IEnumerable(Of TCollection))), _ resultSelector As Expression(Of Func(Of TSource, TCollection, TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> SelectMany\<TSource, TCollection, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, IEnumerable<TCollection>>> collectionSelector, Expression<Func\<TSource, TCollection, TResult>> resultSelector )
SelectMany Non supportato Function SelectMany(Of TSource, TCollection, TResult) ( _ source As IQueryable(Of TSource), _ collectionSelector As Expression(Of Func(Of TSource, Integer, IEnumerable(Of TCollection))), _ resultSelector As Expression(Of Func(Of TSource, TCollection, TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> SelectMany\<TSource, TCollection, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, int, IEnumerable<TCollection>>> collectionSelector, Expression<Func\<TSource, TCollection, TResult>> resultSelector )
Where Supportato Function Where(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> Where<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Where Non supportato Function Where(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Integer, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> Where<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, int, bool>> predicate )

Metodi join

I metodi join LINQ sono supportati in LINQ to Entities, fatta eccezione per i metodi che accettano un oggetto IEqualityComparer, in quanto l'operatore di confronto non può essere convertito nell'origine dati. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di unione supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
GroupJoin Supportato Function GroupJoin(Of TOuter, TInner, TKey, TResult) ( _ outer As IQueryable(Of TOuter), _ inner As IEnumerable(Of TInner), _ outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _ innerKeySelector As Expression(Of Func(Of TInner, TKey)), _ resultSelector As Expression(Of Func(Of TOuter, IEnumerable(Of TInner), TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupJoin<TOuter, TInner, TKey, TResult>( this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector )
GroupJoin Non supportato Function GroupJoin(Of TOuter, TInner, TKey, TResult) ( _ outer As IQueryable(Of TOuter), _ inner As IEnumerable(Of TInner), _ outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _ innerKeySelector As Expression(Of Func(Of TInner, TKey)), _ resultSelector As Expression(Of Func(Of TOuter, IEnumerable(Of TInner), TResult)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupJoin\<TOuter, TInner, TKey, TResult>( this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func\<TOuter, TKey>> outerKeySelector, Expression<Func\<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, IEnumerable<TInner>, TResult>> resultSelector, IEqualityComparer<TKey> comparer )
Join Supportato Function Join(Of TOuter, TInner, TKey, TResult) ( _ outer As IQueryable(Of TOuter), _ inner As IEnumerable(Of TInner), _ outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _ innerKeySelector As Expression(Of Func(Of TInner, TKey)), _ resultSelector As Expression(Of Func(Of TOuter, TInner, TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> Join<TOuter, TInner, TKey, TResult>( this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func<TOuter, TKey>> outerKeySelector, Expression<Func<TInner, TKey>> innerKeySelector, Expression<Func<TOuter, TInner, TResult>> resultSelector )
Join Non supportato Function Join(Of TOuter, TInner, TKey, TResult) ( _ outer As IQueryable(Of TOuter), _ inner As IEnumerable(Of TInner), _ outerKeySelector As Expression(Of Func(Of TOuter, TKey)), _ innerKeySelector As Expression(Of Func(Of TInner, TKey)), _ resultSelector As Expression(Of Func(Of TOuter, TInner, TResult)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of TResult) IQueryable<TResult> Join\<TOuter, TInner, TKey, TResult>( this IQueryable<TOuter> outer, IEnumerable<TInner> inner, Expression<Func\<TOuter, TKey>> outerKeySelector, Expression<Func\<TInner, TKey>> innerKeySelector, Expression<Func\<TOuter, TInner, TResult>> resultSelector, IEqualityComparer<TKey> comparer )

Imposta metodi

La maggior parte dei metodi del set LINQ è supportata nelle query LINQ to Entities, a eccezione di quelle che usano un oggetto EqualityComparer<T>. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi Set supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
All Supportata Function All(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As Boolean bool All<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Any Supportato Function Any(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Boolean bool Any<TSource>( this IQueryable<TSource> source )
Any Supportato Function Any(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As Boolean bool Any<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Contains Supportato Function Contains(Of TSource) ( _ source As IQueryable(Of TSource), _ item As TSource _ ) As Boolean bool Contains<TSource>( this IQueryable<TSource> source, TSource item )
Contains Non supportato Function Contains(Of TSource) ( _ source As IQueryable(Of TSource), _ item As TSource, _ comparer As IEqualityComparer(Of TSource) _ ) As Boolean bool Contains<TSource>( this IQueryable<TSource> source, TSource item, IEqualityComparer<TSource> comparer )
Concat Supportato, ma nessuna garanzia

di ordine mantenuto
Function Concat(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Concat<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2 )
DefaultIfEmpty Supportata Function DefaultIfEmpty(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> DefaultIfEmpty<TSource>( this IQueryable<TSource> source )
DefaultIfEmpty Supportato Function DefaultIfEmpty(Of TSource) ( _ source As IQueryable(Of TSource), _ defaultValue As TSource _ ) As IQueryable(Of TSource) IQueryable<TSource> DefaultIfEmpty<TSource>( this IQueryable<TSource> source, TSource defaultValue )
Distinct Supportato Function Distinct(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Distinct<TSource>( this IQueryable<TSource> source )
Distinct Non supportato Function Distinct(Of TSource) ( _ source As IQueryable(Of TSource), _ comparer As IEqualityComparer(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Distinct<TSource>( this IQueryable<TSource> source, IEqualityComparer<TSource> comparer )
Except Supportato Function Except(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Except<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2 )
Except Non supportato Function Except(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource), _ comparer As IEqualityComparer(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Except<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer )
Intersect Supportato Function Intersect(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Intersect<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2 )
Intersect Non supportato Function Intersect(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource), _ comparer As IEqualityComparer(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Intersect<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer )
Union Supportato Function Union(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Union<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2 )
Union Non supportato Function Union(Of TSource) ( _ source1 As IQueryable(Of TSource), _ source2 As IEnumerable(Of TSource), _ comparer As IEqualityComparer(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Union<TSource>( this IQueryable<TSource> source1, IEnumerable<TSource> source2, IEqualityComparer<TSource> comparer )

Metodi di ordinamento

La maggior parte dei metodi di ordinamento LINQ è supportata in LINQ to Entities, fatta eccezione per i metodi che accettano un oggetto IComparer<T>, in quanto l'operatore di confronto non può essere convertito nell'origine dati. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di ordinamento supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
OrderBy Supportato Function OrderBy(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> OrderBy<TSource, TKey>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
OrderBy Non supportato Function OrderBy(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ comparer As IComparer(Of TKey) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> OrderBy\<TSource, TKey>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, IComparer<TKey> comparer )
OrderByDescending Supportato Function OrderByDescending(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> OrderByDescending<TSource, TKey>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
OrderByDescending Non supportato Function OrderByDescending(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ comparer As IComparer(Of TKey) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> OrderByDescending\<TSource, TKey>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, IComparer<TKey> comparer )
ThenBy Supportato Function ThenBy(Of TSource, TKey) ( _ source As IOrderedQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> ThenBy<TSource, TKey>( this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
ThenBy Non supportato Function ThenBy(Of TSource, TKey) ( _ source As IOrderedQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ comparer As IComparer(Of TKey) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> ThenBy\<TSource, TKey>( this IOrderedQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, IComparer<TKey> comparer )
ThenByDescending Supportato Function ThenByDescending(Of TSource, TKey) ( _ source As IOrderedQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> ThenByDescending<TSource, TKey>( this IOrderedQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
ThenByDescending Non supportato Function ThenByDescending(Of TSource, TKey) ( _ source As IOrderedQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ comparer As IComparer(Of TKey) _ ) As IOrderedQueryable(Of TSource) IOrderedQueryable<TSource> ThenByDescending\<TSource, TKey>( this IOrderedQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, IComparer<TKey> comparer )
Reverse Non supportato Function Reverse(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) IQueryable<TSource> Reverse<TSource>( this IQueryable<TSource> source )

Metodi di raggruppamento

La maggior parte dei metodi di raggruppamento LINQ è supportata in LINQ to Entities, fatta eccezione per i metodi che accettano un oggetto IEqualityComparer<T>, in quanto l'operatore di confronto non può essere convertito nell'origine dati. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di raggruppamento supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
GroupBy Supportato Function GroupBy(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)) _ ) As IQueryable(Of IGrouping(Of TKey, TSource)) IQueryable<IGrouping<TKey, TSource>> GroupBy<TSource, TKey>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector )
GroupBy Non supportato Function GroupBy(Of TSource, TKey) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of IGrouping(Of TKey, TSource)) IQueryable<IGrouping\<TKey, TSource>> GroupBy\<TSource, TKey>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, IEqualityComparer<TKey> comparer )
GroupBy Supportata Function GroupBy(Of TSource, TKey, TElement) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ elementSelector As Expression(Of Func(Of TSource, TElement)) _ ) As IQueryable(Of IGrouping(Of TKey, TElement)) IQueryable<IGrouping<TKey, TElement>> GroupBy<TSource, TKey, TElement>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector )
GroupBy Supportato Function GroupBy(Of TSource, TKey, TResult) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ resultSelector As Expression(Of Func(Of TKey, IEnumerable(Of TSource), TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupBy\<TSource, TKey, TResult>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, Expression<Func<TKey, IEnumerable<TSource>, TResult>> resultSelector )
GroupBy Non supportato Function GroupBy(Of TSource, TKey, TElement) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ elementSelector As Expression(Of Func(Of TSource, TElement)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of IGrouping(Of TKey, TElement)) IQueryable<IGrouping\<TKey, TElement>> GroupBy\<TSource, TKey, TElement>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, Expression<Func\<TSource, TElement>> elementSelector, IEqualityComparer<TKey> comparer
GroupBy Supportato Function GroupBy(Of TSource, TKey, TElement, TResult) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ elementSelector As Expression(Of Func(Of TSource, TElement)), _ resultSelector As Expression(Of Func(Of TKey, IEnumerable(Of TElement), TResult)) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupBy<TSource, TKey, TElement, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector, Expression<Func<TKey, IEnumerable<TElement>, TResult>> resultSelector )
GroupBy Non supportato Function GroupBy(Of TSource, TKey, TResult) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ resultSelector As Expression(Of Func(Of TKey, IEnumerable(Of TSource), TResult)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupBy\<TSource, TKey, TResult>( this IQueryable<TSource> source, Expression<Func\<TSource, TKey>> keySelector, Expression<Func<TKey, IEnumerable<TSource>, TResult>> resultSelector, IEqualityComparer<TKey> comparer )
GroupBy Non supportato Function GroupBy(Of TSource, TKey, TElement, TResult) ( _ source As IQueryable(Of TSource), _ keySelector As Expression(Of Func(Of TSource, TKey)), _ elementSelector As Expression(Of Func(Of TSource, TElement)), _ resultSelector As Expression(Of Func(Of TKey, IEnumerable(Of TElement), TResult)), _ comparer As IEqualityComparer(Of TKey) _ ) As IQueryable(Of TResult) IQueryable<TResult> GroupBy<TSource, TKey, TElement, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, TKey>> keySelector, Expression<Func<TSource, TElement>> elementSelector, Expression<Func<TKey, IEnumerable<TElement>, TResult>> resultSelector, IEqualityComparer<TKey> comparer )

Metodi di aggregazione

In LINQ to Entities è supportata la maggior parte dei metodi di aggregazione che accettano tipi di dati primitivi. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di aggregazione supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
Aggregate Non supportato Function Aggregate(Of TSource) ( _ source As IQueryable(Of TSource), _ func As Expression(Of Func(Of TSource, TSource, TSource)) _ ) As TSource TSource Aggregate<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, TSource, TSource>> func )
Aggregate Non supportato Function Aggregate(Of TSource, TAccumulate) ( _ source As IQueryable(Of TSource), _ seed As TAccumulate, _ func As Expression(Of Func(Of TAccumulate, TSource, TAccumulate)) _ ) As TAccumulate TAccumulate Aggregate<TSource, TAccumulate>( this IQueryable<TSource> source, TAccumulate seed, Expression<Func<TAccumulate, TSource, TAccumulate>> func )
Aggregate Non supportato Function Aggregate(Of TSource, TAccumulate, TResult) ( _ source As IQueryable(Of TSource), _ seed As TAccumulate, _ func As Expression(Of Func(Of TAccumulate, TSource, TAccumulate)), _ selector As Expression(Of Func(Of TAccumulate, TResult)) _ ) As TResult TResult Aggregate<TSource, TAccumulate, TResult>( this IQueryable<TSource> source, TAccumulate seed, Expression<Func<TAccumulate, TSource, TAccumulate>> func, Expression<Func<TAccumulate, TResult>> selector )
Average Supportata Function Average ( _ source As IQueryable(Of Decimal) _ ) As Decimal decimal Average( this IQueryable<decimal> source )
Average Supportato Function Average ( _ source As IQueryable(Of Double) _ ) As Double double Average( this IQueryable<double> source )
Average Supportato Function Average ( _ source As IQueryable(Of Integer) _ ) As Double double Average( this IQueryable<int> source )
Average Supportato Function Average ( _ source As IQueryable(Of Long) _ ) As Double double Average( this IQueryable<long> source )
Average Supportato Function Average ( _ source As IQueryable(Of Nullable(Of Decimal)) _ ) As Nullable(Of Decimal) Nullable<decimal> Average( this IQueryable<Nullable<decimal>> source )
Average Supportato Function Average ( _ source As IQueryable(Of Nullable(Of Double)) _ ) As Nullable(Of Double) Nullable<double> Average( this IQueryable<Nullable<double>> source )
Average Supportato Function Average ( _ source As IQueryable(Of Nullable(Of Integer)) _ ) As Nullable(Of Double) Nullable<double> Average( this IQueryable<Nullable<int>> source )
Average Supportato Function Average ( _ source As IQueryable(Of Nullable(Of Long)) _ ) As Nullable(Of Double) Nullable<double> Average( this IQueryable<Nullable<long>> source )
Average Supportato Function Average ( _ source As IQueryable(Of Nullable(Of Single)) _ ) As Nullable(Of Single) Nullable<float> Average( this IQueryable<Nullable<float>> source )
Average Supportato Function Average ( _ source As IQueryable(Of Single) _ ) As Single float Average( this IQueryable<float> source )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Integer)) _ ) As Double double Average<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, int>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Integer))) _ ) As Nullable(Of Double) Nullable<double> Average<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<int>>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Long)) _ ) As Double double Average<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, long>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Long))) _ ) As Nullable(Of Double) Nullable<double> Average<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<long>>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Single)) _ ) As Single float Average<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, float>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Single))) _ ) As Nullable(Of Single) Nullable<float> Average<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<float>>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Double)) _ ) As Double double Average<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, double>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Double))) _ ) As Nullable(Of Double) Nullable<double> Average<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<double>>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Decimal)) _ ) As Decimal decimal Average<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, decimal>> selector )
Average Non supportato Function Average(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Decimal))) _ ) As Nullable(Of Decimal) Nullable<decimal> Average<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<decimal>>> selector )
Count Supportato Function Count(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Integer int Count<TSource>( this IQueryable<TSource> source )
Count Non supportato Function Count(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As Integer int Count<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
LongCount Supportato Function LongCount(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Long long LongCount<TSource>( this IQueryable<TSource> source )
LongCount Non supportato Function LongCount(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As Long long LongCount<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Max Supportato Function Max(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource Max<TSource>( this IQueryable<TSource> source )
Max Non supportato Function Max(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, TResult)) _ ) As TResult TResult Max<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector )
Min Supportato Function Min(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource Min<TSource>( this IQueryable<TSource> source )
Min Non supportato Function Min(Of TSource, TResult) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, TResult)) _ ) As TResult TResult Min<TSource, TResult>( this IQueryable<TSource> source, Expression<Func<TSource, TResult>> selector )
Sum Supportata Function Sum ( _ source As IQueryable(Of Decimal) _ ) As Decimal decimal Sum( this IQueryable<decimal> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Double) _ ) As Double double Sum( this IQueryable<double> source
Sum Supportato Function Sum ( _ source As IQueryable(Of Integer) _ ) As Integer int Sum( this IQueryable<int> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Long) _ ) As Long long Sum( this IQueryable<long> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Nullable(Of Decimal)) _ ) As Nullable(Of Decimal) Nullable<decimal> Sum( this IQueryable<Nullable<decimal>> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Nullable(Of Double)) _ ) As Nullable(Of Double) Function Sum ( _ source As IQueryable(Of Nullable(Of Double)) _ ) As Nullable(Of Double)Nullable<double> Sum( this IQueryable<Nullable<double>> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Nullable(Of Integer)) _ ) As Nullable(Of Integer) Nullable<int> Sum( this IQueryable<Nullable<int>> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Nullable(Of Long)) _ ) As Nullable(Of Long) Nullable<long> Sum( this IQueryable<Nullable<long>> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Nullable(Of Single)) _ ) As Nullable(Of Single) Nullable<float> Sum( this IQueryable<Nullable<float>> source )
Sum Supportato Function Sum ( _ source As IQueryable(Of Single) _ ) As Single float Sum( this IQueryable<float> source )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Integer)) _ ) As Integer int Sum<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, int>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Integer))) _ ) As Nullable(Of Integer) Nullable<int> Sum<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<int>>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Long)) _ ) As Long long Sum<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, long>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Long))) _ ) As Nullable(Of Long) Nullable<long> Sum<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<long>>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Single))) _ ) As Nullable(Of Single) Nullable<float> Sum<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<float>>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Single)) _ ) As Single float Sum<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, float>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Double)) _ ) As Double double Sum<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, double>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Double))) _ ) As Nullable(Of Double) Nullable<double> Sum<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<double>>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Decimal)) _ ) As Decimal decimal Sum<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, decimal>> selector )
Sum Non supportato Function Sum(Of TSource) ( _ source As IQueryable(Of TSource), _ selector As Expression(Of Func(Of TSource, Nullable(Of Decimal))) _ ) As Nullable(Of Decimal) Nullable<decimal> Sum<TSource>( this IQueryable<TSource> source, Expression<Func<TSource, Nullable<decimal>>> selector )

Metodi di tipo

Gli operatori di query standard LINQ che gestiscono i test e la conversione dei tipi CLR sono supportati in Entity Framework. Solo i tipi CLR mappati ai tipi del modello concettuale sono supportati in LINQ to Entities. Per un elenco dei tipi di modello concettuale, vedere Tipi di modello concettuale (CSDL). Nella tabella seguente sono elencati i metodi di tipo supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
Cast Supportato per i tipi primitivi EDM Function Cast(Of TResult) ( _ source As IQueryable _ ) As IQueryable(Of TResult) IQueryable<TResult> Cast<TResult>( this IQueryable source )
OfType Supportato per EntityType Function OfType(Of TResult) ( _ source As IQueryable _ ) As IQueryable(Of TResult) IQueryable<TResult> OfType<TResult>( this IQueryable source )

Metodi di paging

Alcuni metodi di paging LINQ non sono supportati nelle query LINQ to Entities. Per altre informazioni, vedere Operatori di query standard in query LINQ to Entities. Nella tabella seguente sono elencati i metodi di paging supportati e non supportati.

metodo Supporto tecnico Firma della funzione Visual Basic Firma del metodo C#
ElementAt Non supportato Function ElementAt(Of TSource) ( _ source As IQueryable(Of TSource), _ index As Integer _ ) As TSource TSource ElementAt<TSource>( this IQueryable<TSource> source, int index )
ElementAtOrDefault Non supportato Function ElementAtOrDefault(Of TSource) ( _ source As IQueryable(Of TSource), _ index As Integer _ ) As TSource TSource ElementAtOrDefault<TSource>( this IQueryable<TSource> source, int index )
First Supportata Function First(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource First<TSource>( this IQueryable<TSource> source )
First Supportato Function First(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource First<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
FirstOrDefault Supportato Function FirstOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource FirstOrDefault<TSource>( this IQueryable<TSource> source )
FirstOrDefault Supportato Function FirstOrDefault(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource FirstOrDefault<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Last Non supportato Function Last(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource Last<TSource>( this IQueryable<TSource> source )
Last Non supportato Function Last(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource Last<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
LastOrDefault Non supportato Function LastOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource LastOrDefault<TSource>( this IQueryable<TSource> source )
LastOrDefault Non supportato Function LastOrDefault(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource LastOrDefault<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Single Supportata Function Single(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource Single<TSource>( this IQueryable<TSource> source )
Single Supportato Function Single(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource Single<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
SingleOrDefault Supportato Function SingleOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource TSource SingleOrDefault<TSource>( this IQueryable<TSource> source )
SingleOrDefault Supportato Function SingleOrDefault(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As TSource TSource SingleOrDefault<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
Skip Supportato Function Skip(Of TSource) ( _ source As IQueryable(Of TSource), _ count As Integer _ ) As IQueryable(Of TSource) IQueryable<TSource> Skip<TSource>( this IQueryable<TSource> source, int count )
SkipWhile Non supportato Function SkipWhile(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> SkipWhile<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
SkipWhile Non supportato Function SkipWhile(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Integer, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> SkipWhile<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, int, bool>> predicate )
Take Supportato Function Take(Of TSource) ( _ source As IQueryable(Of TSource), _ count As Integer _ ) As IQueryable(Of TSource) IQueryable<TSource> Take<TSource>( this IQueryable<TSource> source, int count )
TakeWhile Non supportato Function TakeWhile(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> TakeWhile<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, bool>> predicate )
TakeWhile Non supportato Function TakeWhile(Of TSource) ( _ source As IQueryable(Of TSource), _ predicate As Expression(Of Func(Of TSource, Integer, Boolean)) _ ) As IQueryable(Of TSource) IQueryable<TSource> TakeWhile<TSource>( this IQueryable<TSource> source, Expression<Func\<TSource, int, bool>> predicate )

Vedi anche