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 ) |