支援與不支援的 LINQ 方法 (LINQ to Entities)

本章節提供的資訊是有關 LINQ to Entities 查詢所支援或不支援的 Language-Integrated Query (LINQ) 標準查詢運算子。 許多 LINQ 標準查詢運算子都有一個可接受整數引數的多載版本。 此整數引數會對應到所操作之序列 (Sequence) 中以零為起始的索引 (IEqualityComparerIComparer)。 除非另外指定,否則不支援 LINQ 標準查詢運算子的這些多載版本,若嘗試使用,會擲回例外狀況。

投影和限制方法

LINQ to Entities 查詢中支援大部分 LINQ 投影和限制方法,但接受位置引數者除外。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的投影和限制方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

Select

支援項目

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

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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
)

聯結方法

LINQ to Entities 中支援大部分 LINQ 聯結方法,但接受 IEqualityComparer 者除外,因為比較子無法轉譯成資料來源。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的聯結方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

GroupJoin

支援項目

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

不支援

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

支援項目

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

不支援

 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 方法

LINQ to Entities 查詢中支援大部分 LINQ 設定方法,但使用 EqualityComparer 者除外。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的設定方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

All

支援項目

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

支援項目

Function Any(Of TSource) ( _
source As IQueryable(Of TSource) _
) As Boolean
bool Any<TSource>(
this IQueryable<TSource> source
)

Any

支援項目

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

支援項目

Function Contains(Of TSource) ( _
source As IQueryable(Of TSource), _
item As TSource _
) As Boolean
bool Contains<TSource>(
this IQueryable<TSource> source,
TSource item
)

Contains

不支援

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

支援,但是不

保證會維持排序

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

支援項目

Function DefaultIfEmpty(Of TSource) ( _
source As IQueryable(Of TSource) _
) As IQueryable(Of TSource)
IQueryable<TSource> DefaultIfEmpty<TSource>(
this IQueryable<TSource> source
)

DefaultIfEmpty

支援項目

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

支援項目

Function Distinct(Of TSource) ( _
source As IQueryable(Of TSource) _
) As IQueryable(Of TSource)
IQueryable<TSource> Distinct<TSource>(
this IQueryable<TSource> source
)

Distinct

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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
)

排序方法

LINQ to Entities 中支援大部分 LINQ 排序方法,但接受 IComparer 者除外,因為比較子無法轉譯成資料來源。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的排序方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

OrderBy

支援項目

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

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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

支援項目

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

不支援

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

不支援

Function Reverse(Of TSource) ( _
source As IQueryable(Of TSource) _
) As IQueryable(Of TSource)
IQueryable<TSource> Reverse<TSource>(
this IQueryable<TSource> source
)

群組方法

LINQ to Entities 中支援大部分 LINQ 群組方法,但接受 IEqualityComparer 者除外,因為比較子無法轉譯成資料來源。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的群組方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

GroupBy

支援項目

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

不支援

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

支援項目

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

支援項目

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

不支援

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

支援項目

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

不支援

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

不支援

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
)

彙總方法

LINQ to Entities 中支援大部分接受基本資料型別的彙總方法。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援及不支援的彙總方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

Aggregate

不支援

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

不支援

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

不支援

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

支援項目

Function Average ( _
source As IQueryable(Of Decimal) _
) As Decimal
decimal Average(
this IQueryable<decimal> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Double) _
) As Double
double Average(
this IQueryable<double> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Integer) _
) As Double
double Average(
this IQueryable<int> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Long) _
) As Double
double Average(
this IQueryable<long> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Nullable(Of Decimal)) _
) As Nullable(Of Decimal)
Nullable<decimal> Average(
this IQueryable<Nullable<decimal>> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Nullable(Of Double)) _
) As Nullable(Of Double)
Nullable<double> Average(
this IQueryable<Nullable<double>> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Nullable(Of Integer)) _
) As Nullable(Of Double)
Nullable<double> Average(
this IQueryable<Nullable<int>> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Nullable(Of Long)) _
) As Nullable(Of Double)
Nullable<double> Average(
this IQueryable<Nullable<long>> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Nullable(Of Single)) _
) As Nullable(Of Single)
Nullable<float> Average(
this IQueryable<Nullable<float>> source
)

Average

支援項目

Function Average ( _
source As IQueryable(Of Single) _
) As Single
float Average(
this IQueryable<float> source
)

Average

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

支援項目

Function Count(Of TSource) ( _
source As IQueryable(Of TSource) _
) As Integer
int Count<TSource>(
this IQueryable<TSource> source
)

Count

不支援

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

支援項目

Function LongCount(Of TSource) ( _
source As IQueryable(Of TSource) _
) As Long
long LongCount<TSource>(
this IQueryable<TSource> source
)

LongCount

不支援

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

支援項目

Function Max(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource Max<TSource>(
this IQueryable<TSource> source
)

Max

不支援

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

支援項目

Function Min(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource Min<TSource>(
this IQueryable<TSource> source
)

Min

不支援

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

支援項目

Function Sum ( _
source As IQueryable(Of Decimal) _
) As Decimal
decimal Sum(
this IQueryable<decimal> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Double) _
) As Double
double Sum(
this IQueryable<double> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Integer) _
) As Integer
int Sum(
this IQueryable<int> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Long) _
) As Long
long Sum(
this IQueryable<long> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Nullable(Of Decimal)) _
) As Nullable(Of Decimal)
Nullable<decimal> Sum(
this IQueryable<Nullable<decimal>> source
)

Sum

支援項目

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

支援項目

Function Sum ( _
source As IQueryable(Of Nullable(Of Integer)) _
) As Nullable(Of Integer)
Nullable<int> Sum(
this IQueryable<Nullable<int>> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Nullable(Of Long)) _
) As Nullable(Of Long)
Nullable<long> Sum(
this IQueryable<Nullable<long>> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Nullable(Of Single)) _
) As Nullable(Of Single)
Nullable<float> Sum(
this IQueryable<Nullable<float>> source
)

Sum

支援項目

Function Sum ( _
source As IQueryable(Of Single) _
) As Single
float Sum(
this IQueryable<float> source
)

Sum

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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

不支援

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
)

型別方法

Entity Framework 中支援處理 CLR 型別轉換和測試的 LINQ 標準查詢運算子。 LINQ to Entities 中僅支援對應到概念模型型別的 CLR 型別。 如需概念模型型別的清單,請參閱概念模型型別. 以下資料表所列為支援及不支援的型別方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

Cast

支援 EDM 基本型別

Function Cast(Of TResult) ( _
source As IQueryable _
) As IQueryable(Of TResult)
IQueryable<TResult> Cast<TResult>(
this IQueryable source
)

OfType

支援 EntityType

Function OfType(Of TResult) ( _
source As IQueryable _
) As IQueryable(Of TResult)
IQueryable<TResult> OfType<TResult>(
this IQueryable source
)

分頁方法

在 LINQ to Entities 查詢中不支援許多 LINQ 分頁方法。 如需詳細資訊,請參閱 LINQ to Entities 查詢中的標準查詢運算子。 以下資料表所列為支援和不支援的分頁方法。

方法 支援 Visual Basic 函式簽章 C# 方法簽章

ElementAt

不支援

Function ElementAt(Of TSource) ( _
source As IQueryable(Of TSource), _
index As Integer _
) As TSource
TSource ElementAt<TSource>(
this IQueryable<TSource> source,
int index
)

ElementAtOrDefault

不支援

Function ElementAtOrDefault(Of TSource) ( _
source As IQueryable(Of TSource), _
index As Integer _
) As TSource
TSource ElementAtOrDefault<TSource>(
this IQueryable<TSource> source,
int index
)

First

支援項目

Function First(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource First<TSource>(
this IQueryable<TSource> source
)

First

支援項目

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

支援項目

Function FirstOrDefault(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource FirstOrDefault<TSource>(
this IQueryable<TSource> source
)

FirstOrDefault

支援項目

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

不支援

Function Last(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource Last<TSource>(
this IQueryable<TSource> source
)

Last

不支援

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

不支援

Function LastOrDefault(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource LastOrDefault<TSource>(
this IQueryable<TSource> source
)

LastOrDefault

不支援

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

支援項目

Function Single(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource Single<TSource>(
this IQueryable<TSource> source
)

Single

支援項目

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

支援項目

Function SingleOrDefault(Of TSource) ( _
source As IQueryable(Of TSource) _
) As TSource
TSource SingleOrDefault<TSource>(
this IQueryable<TSource> source
)

SingleOrDefault

支援項目

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

支援項目

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

不支援

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

不支援

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

支援項目

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

不支援

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

不支援

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
)

另請參閱

概念

LINQ to Entities 查詢中的標準查詢運算子