Queryable.Intersect Method

Definition

Namespace:

System.Linq

Assembly:

System.Linq.Queryable.dll

Produces the set intersection of two sequences.

Overloads

Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>)	Produces the set intersection of two sequences by using the default equality comparer to compare values.
Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)	Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.

Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>)

Source:

Queryable.cs

Produces the set intersection of two sequences by using the default equality comparer to compare values.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::IQueryable<TSource> ^ Intersect(System::Linq::IQueryable<TSource> ^ source1, System::Collections::Generic::IEnumerable<TSource> ^ source2);

public static System.Linq.IQueryable<TSource> Intersect<TSource> (this System.Linq.IQueryable<TSource> source1, System.Collections.Generic.IEnumerable<TSource> source2);

static member Intersect : System.Linq.IQueryable<'Source> * seq<'Source> -> System.Linq.IQueryable<'Source>

<Extension()>
Public Function Intersect(Of TSource) (source1 As IQueryable(Of TSource), source2 As IEnumerable(Of TSource)) As IQueryable(Of TSource)

Type Parameters

TSource

The type of the elements of the input sequences.

Parameters

source1

IQueryable<TSource>

A sequence whose distinct elements that also appear in source2 are returned.

source2

IEnumerable<TSource>

A sequence whose distinct elements that also appear in the first sequence are returned.

Returns

IQueryable<TSource>

A sequence that contains the set intersection of the two sequences.

Exceptions

ArgumentNullException

source1 or source2 is null.

Examples

The following code example demonstrates how to use Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>) to return the elements that appear in each of two sequences.

int[] id1 = { 44, 26, 92, 30, 71, 38 };
int[] id2 = { 39, 59, 83, 47, 26, 4, 30 };

// Get the numbers that occur in both arrays (id1 and id2).
IEnumerable<int> both = id1.AsQueryable().Intersect(id2);

foreach (int id in both)
    Console.WriteLine(id);

/*
    This code produces the following output:

    26
    30
*/

Dim id1() As Integer = {44, 26, 92, 30, 71, 38}
Dim id2() As Integer = {39, 59, 83, 47, 26, 4, 30}

' Get the numbers that occur in both arrays (id1 and id2).
Dim both As IEnumerable(Of Integer) = id1.AsQueryable().Intersect(id2)

Dim output As New System.Text.StringBuilder
For Each id As Integer In both
    output.AppendLine(id)
Next

' Display the output.
MsgBox(output.ToString())

' This code produces the following output:

' 26
' 30

Remarks

The Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>) method generates a MethodCallExpression that represents calling Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>) itself as a constructed generic method. It then passes the MethodCallExpression to the CreateQuery<TElement>(Expression) method of the IQueryProvider represented by the Provider property of the source1 parameter.

The query behavior that occurs as a result of executing an expression tree that represents calling Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>) depends on the implementation of the type of the source1 parameter. The expected behavior is that all the elements in source1 that are also in source2 are returned.

Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>)

Source:

Queryable.cs

Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.

public:
generic <typename TSource>
[System::Runtime::CompilerServices::Extension]
 static System::Linq::IQueryable<TSource> ^ Intersect(System::Linq::IQueryable<TSource> ^ source1, System::Collections::Generic::IEnumerable<TSource> ^ source2, System::Collections::Generic::IEqualityComparer<TSource> ^ comparer);

public static System.Linq.IQueryable<TSource> Intersect<TSource> (this System.Linq.IQueryable<TSource> source1, System.Collections.Generic.IEnumerable<TSource> source2, System.Collections.Generic.IEqualityComparer<TSource>? comparer);

static member Intersect : System.Linq.IQueryable<'Source> * seq<'Source> * System.Collections.Generic.IEqualityComparer<'Source> -> System.Linq.IQueryable<'Source>

<Extension()>
Public Function Intersect(Of TSource) (source1 As IQueryable(Of TSource), source2 As IEnumerable(Of TSource), comparer As IEqualityComparer(Of TSource)) As IQueryable(Of TSource)

Type Parameters

TSource

The type of the elements of the input sequences.

Parameters

source1

IQueryable<TSource>

An IQueryable<T> whose distinct elements that also appear in source2 are returned.

source2

IEnumerable<TSource>

An IEnumerable<T> whose distinct elements that also appear in the first sequence are returned.

comparer

IEqualityComparer<TSource>

An IEqualityComparer<T> to compare values.

Returns

IQueryable<TSource>

An IQueryable<T> that contains the set intersection of the two sequences.

Exceptions

ArgumentNullException

source1 or source2 is null.

Remarks

The Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>) method generates a MethodCallExpression that represents calling Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>) itself as a constructed generic method. It then passes the MethodCallExpression to the CreateQuery<TElement>(Expression) method of the IQueryProvider represented by the Provider property of the source1 parameter.

The query behavior that occurs as a result of executing an expression tree that represents calling Intersect<TSource>(IQueryable<TSource>, IEnumerable<TSource>, IEqualityComparer<TSource>) depends on the implementation of the type of the source1 parameter. The expected behavior is that all the elements in source1 that are also in source2 are returned. The comparer parameter is used to compare elements.