Enumerable.Intersect Enumerable.Intersect Enumerable.Intersect Enumerable.Intersect Method

정의

두 시퀀스의 교집합을 구합니다.Produces the set intersection of two sequences.

오버로드

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

지정 된 사용 하 여 두 시퀀스의 교집합을 구합니다 IEqualityComparer<T> 값을 비교 합니다.Produces the set intersection of two sequences by using the specified IEqualityComparer<T> to compare values.

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

기본 같음 비교자를 사용 하 여 값을 비교 하 여 두 시퀀스의 교집합을 구합니다.Produces the set intersection of two sequences by using the default equality comparer to compare values.

설명

참고

이 문서의 일부 C# 예제는 Try.NET 인라인 코드 실행기 및 플레이그라운드에서 실행됩니다.Some of the C# examples in this article run in the Try.NET inline code runner and playground. 대화형 창에서 예제를 실행하려면 실행 단추(있는 경우)를 선택합니다.When present, select the Run button to run an example in an interactive window. 코드를 실행하면 실행을 다시 선택하여 코드를 수정하고 수정된 코드를 실행할 수 있습니다.Once you execute the code, you can modify it and run the modified code by selecting Run again. 수정된 코드는 대화형 창에서 실행되거나, 컴파일이 실패하면 대화형 창에 모든 C# 컴파일러 오류 메시지가 표시됩니다.The modified code either runs in the interactive window or, if compilation fails, the interactive window displays all C# compiler error messages.

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

지정 된 사용 하 여 두 시퀀스의 교집합을 구합니다 IEqualityComparer<T> 값을 비교 합니다.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::Collections::Generic::IEnumerable<TSource> ^ Intersect(System::Collections::Generic::IEnumerable<TSource> ^ first, System::Collections::Generic::IEnumerable<TSource> ^ second, System::Collections::Generic::IEqualityComparer<TSource> ^ comparer);
public static System.Collections.Generic.IEnumerable<TSource> Intersect<TSource> (this System.Collections.Generic.IEnumerable<TSource> first, System.Collections.Generic.IEnumerable<TSource> second, System.Collections.Generic.IEqualityComparer<TSource> comparer);
static member Intersect : seq<'Source> * seq<'Source> * System.Collections.Generic.IEqualityComparer<'Source> -> seq<'Source>
<Extension()>
Public Function Intersect(Of TSource) (first As IEnumerable(Of TSource), second As IEnumerable(Of TSource), comparer As IEqualityComparer(Of TSource)) As IEnumerable(Of TSource)

형식 매개 변수

TSource

입력 시퀀스 요소의 형식입니다.The type of the elements of the input sequences.

매개 변수

first
IEnumerable<TSource>

IEnumerable<T> 에 있는 고유 요소가 second 반환 됩니다.An IEnumerable<T> whose distinct elements that also appear in second will be returned.

second
IEnumerable<TSource>

IEnumerable<T> 첫 번째 시퀀스에도 있는 고유 요소가 반환 됩니다.An IEnumerable<T> whose distinct elements that also appear in the first sequence will be returned.

comparer
IEqualityComparer<TSource>

IEqualityComparer<T> 값을 비교 합니다.An IEqualityComparer<T> to compare values.

반환

IEnumerable<TSource>

두 시퀀스의 교집합을 이루는 요소가 들어 있는 시퀀스입니다.A sequence that contains the elements that form the set intersection of two sequences.

예외

first 또는 secondnull인 경우first or second is null.

예제

다음 예제에서는에서 사용할 수 있는 같음 비교자를 구현 하는 방법을 보여 줍니다는 Intersect 메서드.The following example shows how to implement an equality comparer that can be used in the Intersect method.

public class Product
{
    public string Name { get; set; }
    public int Code { get; set; }
}

// Custom comparer for the Product class
class ProductComparer : IEqualityComparer<Product>
{
    // Products are equal if their names and product numbers are equal.
    public bool Equals(Product x, Product y)
    {
       
        //Check whether the compared objects reference the same data.
        if (Object.ReferenceEquals(x, y)) return true;

        //Check whether any of the compared objects is null.
        if (Object.ReferenceEquals(x, null) || Object.ReferenceEquals(y, null))
            return false;

        //Check whether the products' properties are equal.
        return x.Code == y.Code && x.Name == y.Name;
    }

    // If Equals() returns true for a pair of objects 
    // then GetHashCode() must return the same value for these objects.

    public int GetHashCode(Product product)
    {
        //Check whether the object is null
        if (Object.ReferenceEquals(product, null)) return 0;

        //Get hash code for the Name field if it is not null.
        int hashProductName = product.Name == null ? 0 : product.Name.GetHashCode();

        //Get hash code for the Code field.
        int hashProductCode = product.Code.GetHashCode();

        //Calculate the hash code for the product.
        return hashProductName ^ hashProductCode;
    }

}
Public Class Product
    Public Property Name As String
    Public Property Code As Integer
End Class

' Custom comparer for the Product class
Public Class ProductComparer
    Implements IEqualityComparer(Of Product)

    Public Function Equals1(
        ByVal x As Product, 
        ByVal y As Product
        ) As Boolean Implements IEqualityComparer(Of Product).Equals

        ' Check whether the compared objects reference the same data.
        If x Is y Then Return True

        'Check whether any of the compared objects is null.
        If x Is Nothing OrElse y Is Nothing Then Return False

        ' Check whether the products' properties are equal.
        Return (x.Code = y.Code) AndAlso (x.Name = y.Name)
    End Function

    Public Function GetHashCode1(
        ByVal product As Product
        ) As Integer Implements IEqualityComparer(Of Product).GetHashCode

        ' Check whether the object is null.
        If product Is Nothing Then Return 0

        ' Get hash code for the Name field if it is not null.
        Dim hashProductName = 
            If(product.Name Is Nothing, 0, product.Name.GetHashCode())

        ' Get hash code for the Code field.
        Dim hashProductCode = product.Code.GetHashCode()

        ' Calculate the hash code for the product.
        Return hashProductName Xor hashProductCode
    End Function
End Class

이 비교자를 구현한 후의 시퀀스를 사용할 수 있습니다 Product 개체는 Intersect 메서드를 다음 예제에서와 같이:After you implement this comparer, you can use sequences of Product objects in the Intersect method, as shown in the following example:

Product[] store1 = { new Product { Name = "apple", Code = 9 }, 
                       new Product { Name = "orange", Code = 4 } };

Product[] store2 = { new Product { Name = "apple", Code = 9 }, 
                       new Product { Name = "lemon", Code = 12 } };
Dim store1() As Product = 
    {New Product With {.Name = "apple", .Code = 9}, 
     New Product With {.Name = "orange", .Code = 4}}

Dim store2() As Product = 
    {New Product With {.Name = "apple", .Code = 9}, 
     New Product With {.Name = "lemon", .Code = 12}}
// Get the products from the first array 
// that have duplicates in the second array.

IEnumerable<Product> duplicates =
    store1.Intersect(store2, new ProductComparer());

foreach (var product in duplicates)
    Console.WriteLine(product.Name + " " + product.Code);

/*
    This code produces the following output:
    apple 9
*/
' Get the products from the first array 
' that have duplicates in the second array.

Dim duplicates = store1.Intersect(store2, New ProductComparer())

For Each product In duplicates
    Console.WriteLine(product.Name & " " & product.Code)
Next

' This code produces the following output:
'
' apple 9
' 

설명

이 메서드는 지연 된 실행을 사용 하 여 구현 됩니다.This method is implemented by using deferred execution. 즉시 반환 값은 작업을 수행 하는 데 필요한 모든 정보를 저장 하는 개체입니다.The immediate return value is an object that stores all the information that is required to perform the action. 이 메서드를 나타내는 쿼리 하거나 호출 하 여 개체 열거 될 때까지 실행 되지 않습니다 해당 GetEnumerator 메서드를 사용 하 여 직접 또는 foreach Visual C# 또는 For Each Visual Basic의 합니다.The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in Visual C# or For Each in Visual Basic.

A와 B에는 두 집합의 교집합은 있지만 다른 요소는 또한 B에 표시 되는 모든 요소를 포함 하는 집합으로 정의 됩니다.The intersection of two sets A and B is defined as the set that contains all the elements of A that also appear in B, but no other elements.

이 메서드에서 반환 되는 개체를 열거 하면 Intersect 에 나타나는 순서 대로 두 시퀀스에서 발생 하는 고유 요소를 생성 first합니다.When the object returned by this method is enumerated, Intersect yields distinct elements occurring in both sequences in the order in which they appear in first.

하는 경우 comparer 됩니다 null, 기본 같음 비교자를 Default, 값을 비교 하는 데 사용 됩니다.If comparer is null, the default equality comparer, Default, is used to compare values.

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

기본 같음 비교자를 사용 하 여 값을 비교 하 여 두 시퀀스의 교집합을 구합니다.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::Collections::Generic::IEnumerable<TSource> ^ Intersect(System::Collections::Generic::IEnumerable<TSource> ^ first, System::Collections::Generic::IEnumerable<TSource> ^ second);
public static System.Collections.Generic.IEnumerable<TSource> Intersect<TSource> (this System.Collections.Generic.IEnumerable<TSource> first, System.Collections.Generic.IEnumerable<TSource> second);
static member Intersect : seq<'Source> * seq<'Source> -> seq<'Source>
<Extension()>
Public Function Intersect(Of TSource) (first As IEnumerable(Of TSource), second As IEnumerable(Of TSource)) As IEnumerable(Of TSource)

형식 매개 변수

TSource

입력 시퀀스 요소의 형식입니다.The type of the elements of the input sequences.

매개 변수

first
IEnumerable<TSource>

IEnumerable<T> 에 있는 고유 요소가 second 반환 됩니다.An IEnumerable<T> whose distinct elements that also appear in second will be returned.

second
IEnumerable<TSource>

IEnumerable<T> 첫 번째 시퀀스에도 있는 고유 요소가 반환 됩니다.An IEnumerable<T> whose distinct elements that also appear in the first sequence will be returned.

반환

IEnumerable<TSource>

두 시퀀스의 교집합을 이루는 요소가 들어 있는 시퀀스입니다.A sequence that contains the elements that form the set intersection of two sequences.

예외

first 또는 secondnull인 경우first or second is null.

예제

다음 코드 예제에 사용 하는 방법을 보여 줍니다. Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>) 정수의 두 시퀀스의 각 표시 되는 요소를 반환 합니다.The following code example demonstrates how to use Intersect<TSource>(IEnumerable<TSource>, IEnumerable<TSource>) to return the elements that appear in each of two sequences of integers.

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

IEnumerable<int> both = id1.Intersect(id2);

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

/*
 This code produces the following output:

 26
 30
*/
' Create two integer arrays.
Dim id1() As Integer = {44, 26, 92, 30, 71, 38}
Dim id2() As Integer = {39, 59, 83, 47, 26, 4, 30}

' Find the set intersection of the two arrays.
Dim intersection As IEnumerable(Of Integer) = id1.Intersect(id2)

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

' Display the output.
MsgBox(output.ToString)

' This code produces the following output:
'
' 26
' 30

구현 해야 하는 일부 사용자 지정 데이터 형식 개체의 시퀀스를 비교 하려는 경우는 IEquatable<T> 도우미 클래스에서 제네릭 인터페이스입니다.If you want to compare sequences of objects of some custom data type, you have to implement the IEquatable<T> generic interface in a helper class. 다음 코드 예제에서는 사용자 지정 데이터 형식에서이 인터페이스를 구현 하 고 재정의 하는 방법을 보여 줍니다 GetHashCodeEquals 메서드.The following code example shows how to implement this interface in a custom data type and override GetHashCode and Equals methods.

public class ProductA: IEquatable<ProductA>
{
    public string Name { get; set; }
    public int Code { get; set; }

    public bool Equals(ProductA other)
    {
        if (other is null)
            return false;

        return this.Name == other.Name && this.Code == other.Code;
    }

    public override bool Equals(object obj) => Equals(obj as ProductA);
    public override int GetHashCode() => (Name, Code).GetHashCode();
}
Public Class ProductA
    Inherits IEquatable(Of ProductA)

    Public Property Name As String
    Public Property Code As Integer

    Public Function Equals(ByVal other As ProductA) As Boolean
        If other Is Nothing Then Return False
        Return Me.Name = other.Name AndAlso Me.Code = other.Code
    End Function

    Public Overrides Function Equals(ByVal obj As Object) As Boolean
        Return Equals(TryCast(obj, ProductA))
    End Function

    Public Overrides Function GetHashCode() As Integer
        Return (Name, Code).GetHashCode()
    End Function

End Class

이 인터페이스를 구현한 후의 시퀀스를 사용할 수 있습니다 ProductA 개체는 Intersect 메서드를 다음 예제에서와 같이:After you implement this interface, you can use sequences of ProductA objects in the Intersect method, as shown in the following example:

ProductA[] store1 = { new ProductA { Name = "apple", Code = 9 }, 
                       new ProductA { Name = "orange", Code = 4 } };

ProductA[] store2 = { new ProductA { Name = "apple", Code = 9 }, 
                       new ProductA { Name = "lemon", Code = 12 } };
Dim store1() As ProductA = 
    {New Product With {.Name = "apple", .Code = 9}, 
     New Product With {.Name = "orange", .Code = 4}}

Dim store2() As ProductA = 
    {New Product With {.Name = "apple", .Code = 9}, 
     New Product With {.Name = "lemon", .Code = 12}}
// Get the products from the first array 
// that have duplicates in the second array.

IEnumerable<ProductA> duplicates =
    store1.Intersect(store2);

foreach (var product in duplicates)
    Console.WriteLine(product.Name + " " + product.Code);

/*
    This code produces the following output:
    apple 9
*/
' Get the products from the first array 
' that have duplicates in the second array.

Dim duplicates = store1.Intersect(store2)

For Each product In duplicates
    Console.WriteLine(product.Name & " " & product.Code)
Next

' This code produces the following output:
'
' apple 9
' 

설명

이 메서드는 지연 된 실행을 사용 하 여 구현 됩니다.This method is implemented by using deferred execution. 즉시 반환 값은 작업을 수행 하는 데 필요한 모든 정보를 저장 하는 개체입니다.The immediate return value is an object that stores all the information that is required to perform the action. 이 메서드를 나타내는 쿼리 하거나 호출 하 여 개체 열거 될 때까지 실행 되지 않습니다 해당 GetEnumerator 메서드를 사용 하 여 직접 또는 foreach Visual C# 또는 For Each Visual Basic의 합니다.The query represented by this method is not executed until the object is enumerated either by calling its GetEnumerator method directly or by using foreach in Visual C# or For Each in Visual Basic.

A와 B에는 두 집합의 교집합은 있지만 다른 요소는 또한 B에 표시 되는 모든 요소를 포함 하는 집합으로 정의 됩니다.The intersection of two sets A and B is defined as the set that contains all the elements of A that also appear in B, but no other elements.

이 메서드에서 반환 되는 개체를 열거 하면 Intersect 에 나타나는 순서 대로 두 시퀀스에서 발생 하는 고유 요소를 생성 first합니다.When the object returned by this method is enumerated, Intersect yields distinct elements occurring in both sequences in the order in which they appear in first.

기본 같음 비교자를 Default, 형식의 값을 비교 하는 데 사용 됩니다.The default equality comparer, Default, is used to compare values of the types. 사용자 지정 데이터 형식 비교를 재정의 해야 합니다 EqualsGetHashCode 메서드를 하 고 필요에 따라 구현 합니다 IEquatable<T> 사용자 지정 형식에서 제네릭 인터페이스입니다.To compare a custom data type, you need to override the Equals and the GetHashCode methods, and optionally implement the IEquatable<T> generic interface in the custom type. 자세한 내용은 Default 속성을 참조하세요.For more information, see the Default property.

적용 대상