Podporované a nepodporované metody LINQ (LINQ to Entities)
Tato část obsahuje informace o standardních dotazech LINQ (Language-Integrated Query), které jsou podporované nebo nepodporované v dotazech LINQ to Entities. Mnoho standardních operátorů dotazu LINQ má přetíženou verzi, která přijímá celočíselné argumenty. Celočíselná hodnota odpovídá indexu založenému na nule v sekvenci, na které se pracuje, nebo IEqualityComparer<T>IComparer<T>. Pokud není uvedeno jinak, tyto přetížené verze standardních operátorů dotazu LINQ nejsou podporovány a při pokusu o jejich použití dojde k výjimce.
Metody projekce a omezení
Většina metod projekce LINQ a omezení se podporuje v dotazech LINQ to Entities s výjimkou těch, které přijímají poziční argument. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody projekce a omezení.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| Select | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 ) |
Metody join
Metody LINQ join jsou podporovány v LINQ to Entities, s výjimkou těch, které přijímají IEqualityComparer , protože porovnávač nelze přeložit do zdroje dat. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody spojení.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| GroupJoin | Podporováno | 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 | Nepodporuje se | 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 | Podporováno | 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 | Nepodporuje se | 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 ) |
Set – metody
Většina metod sady LINQ se podporuje v dotazech LINQ to Entities s výjimkou těch, které používají EqualityComparer<T>. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody sady.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| All | Podporováno | 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 | Podporováno | Function Any(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Boolean |
bool Any<TSource>( this IQueryable<TSource> source ) |
| Any | Podporováno | 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 | Podporováno | Function Contains(Of TSource) ( _ source As IQueryable(Of TSource), _ item As TSource _ ) As Boolean |
bool Contains<TSource>( this IQueryable<TSource> source, TSource item ) |
| Contains | Nepodporováno | 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 | Podporováno, ale neexistuje žádná záruku zachování objednávky |
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 | Podporováno | Function DefaultIfEmpty(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) |
IQueryable<TSource> DefaultIfEmpty<TSource>( this IQueryable<TSource> source ) |
| DefaultIfEmpty | Podporováno | 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 | Podporováno | Function Distinct(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) |
IQueryable<TSource> Distinct<TSource>( this IQueryable<TSource> source ) |
| Distinct | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 ) |
Metody řazení
Většina metod řazení LINQ je podporována v LINQ to Entities, s výjimkou těch, které přijímají IComparer<T>, protože porovnávač nelze přeložit do zdroje dat. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody řazení.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| OrderBy | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Nepodporováno | Function Reverse(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As IQueryable(Of TSource) |
IQueryable<TSource> Reverse<TSource>( this IQueryable<TSource> source ) |
Metody seskupení
Většina metod seskupení LINQ je podporována v LINQ to Entities s výjimkou těch, které přijímají IEqualityComparer<T>, protože porovnávač nelze přeložit do zdroje dat. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody seskupení.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| GroupBy | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 ) |
Agregační metody
Většina agregačních metod, které přijímají primitivní datové typy, jsou podporovány v LINQ to Entities. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované agregační metody.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| Aggregate | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Podporováno | Function Average ( _ source As IQueryable(Of Decimal) _ ) As Decimal |
decimal Average( this IQueryable<decimal> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Double) _ ) As Double |
double Average( this IQueryable<double> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Integer) _ ) As Double |
double Average( this IQueryable<int> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Long) _ ) As Double |
double Average( this IQueryable<long> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Nullable(Of Decimal)) _ ) As Nullable(Of Decimal) |
Nullable<decimal> Average( this IQueryable<Nullable<decimal>> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Nullable(Of Double)) _ ) As Nullable(Of Double) |
Nullable<double> Average( this IQueryable<Nullable<double>> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Nullable(Of Integer)) _ ) As Nullable(Of Double) |
Nullable<double> Average( this IQueryable<Nullable<int>> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Nullable(Of Long)) _ ) As Nullable(Of Double) |
Nullable<double> Average( this IQueryable<Nullable<long>> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Nullable(Of Single)) _ ) As Nullable(Of Single) |
Nullable<float> Average( this IQueryable<Nullable<float>> source ) |
| Average | Podporováno | Function Average ( _ source As IQueryable(Of Single) _ ) As Single |
float Average( this IQueryable<float> source ) |
| Average | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Podporováno | Function Count(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Integer |
int Count<TSource>( this IQueryable<TSource> source ) |
| Count | Nepodporováno | 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 | Podporováno | Function LongCount(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As Long |
long LongCount<TSource>( this IQueryable<TSource> source ) |
| LongCount | Nepodporováno | 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 | Podporováno | Function Max(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource Max<TSource>( this IQueryable<TSource> source ) |
| Max | Nepodporováno | 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 | Podporováno | Function Min(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource Min<TSource>( this IQueryable<TSource> source ) |
| Min | Nepodporováno | 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 | Podporováno | Function Sum ( _ source As IQueryable(Of Decimal) _ ) As Decimal |
decimal Sum( this IQueryable<decimal> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Double) _ ) As Double |
double Sum( this IQueryable<double> source |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Integer) _ ) As Integer |
int Sum( this IQueryable<int> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Long) _ ) As Long |
long Sum( this IQueryable<long> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Nullable(Of Decimal)) _ ) As Nullable(Of Decimal) |
Nullable<decimal> Sum( this IQueryable<Nullable<decimal>> source ) |
| Sum | Podporováno | 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 | Podporováno | Function Sum ( _ source As IQueryable(Of Nullable(Of Integer)) _ ) As Nullable(Of Integer) |
Nullable<int> Sum( this IQueryable<Nullable<int>> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Nullable(Of Long)) _ ) As Nullable(Of Long) |
Nullable<long> Sum( this IQueryable<Nullable<long>> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Nullable(Of Single)) _ ) As Nullable(Of Single) |
Nullable<float> Sum( this IQueryable<Nullable<float>> source ) |
| Sum | Podporováno | Function Sum ( _ source As IQueryable(Of Single) _ ) As Single |
float Sum( this IQueryable<float> source ) |
| Sum | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 ) |
Metody typů
Standardní operátory dotazů LINQ, které pracují s převodem a testováním typu CLR, jsou podporovány v Rozhraní Entity Framework. V LINQ to Entities jsou podporovány pouze typy CLR, které se mapují na koncepční typy modelů. Seznam koncepčních typů modelů najdete v tématu Koncepční typy modelů (CSDL). Následující tabulka uvádí podporované a nepodporované metody typu.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| Cast | Podporováno pro primitivní typy EDM | Function Cast(Of TResult) ( _ source As IQueryable _ ) As IQueryable(Of TResult) |
IQueryable<TResult> Cast<TResult>( this IQueryable source ) |
| OfType | Podporováno pro EntityType | Function OfType(Of TResult) ( _ source As IQueryable _ ) As IQueryable(Of TResult) |
IQueryable<TResult> OfType<TResult>( this IQueryable source ) |
Metody stránkování
V dotazech LINQ to Entities se nepodporuje řada metod stránkování LINQ. Další informace najdete v tématu Standardní operátory dotazů v LINQ to Entities Querys. Následující tabulka uvádí podporované a nepodporované metody stránkování.
| metoda | Technická podpora | Podpis funkce jazyka Visual Basic | Podpis metody jazyka C# |
|---|---|---|---|
| ElementAt | Nepodporováno | Function ElementAt(Of TSource) ( _ source As IQueryable(Of TSource), _ index As Integer _ ) As TSource |
TSource ElementAt<TSource>( this IQueryable<TSource> source, int index ) |
| ElementAtOrDefault | Nepodporováno | Function ElementAtOrDefault(Of TSource) ( _ source As IQueryable(Of TSource), _ index As Integer _ ) As TSource |
TSource ElementAtOrDefault<TSource>( this IQueryable<TSource> source, int index ) |
| First | Podporováno | Function First(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource First<TSource>( this IQueryable<TSource> source ) |
| First | Podporováno | 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 | Podporováno | Function FirstOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource FirstOrDefault<TSource>( this IQueryable<TSource> source ) |
| FirstOrDefault | Podporováno | 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 | Nepodporováno | Function Last(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource Last<TSource>( this IQueryable<TSource> source ) |
| Last | Nepodporováno | 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 | Nepodporováno | Function LastOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource LastOrDefault<TSource>( this IQueryable<TSource> source ) |
| LastOrDefault | Nepodporováno | 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 | Podporováno | Function Single(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource Single<TSource>( this IQueryable<TSource> source ) |
| Single | Podporováno | 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 | Podporováno | Function SingleOrDefault(Of TSource) ( _ source As IQueryable(Of TSource) _ ) As TSource |
TSource SingleOrDefault<TSource>( this IQueryable<TSource> source ) |
| SingleOrDefault | Podporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 | Podporováno | 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 | Nepodporováno | 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 | Nepodporováno | 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 ) |