IEnumerable 인터페이스

정의

제네릭이 아닌 컬렉션에서 단순하게 반복할 수 있도록 지원하는 열거자를 노출합니다.Exposes an enumerator, which supports a simple iteration over a non-generic collection.

public interface class IEnumerable
public interface IEnumerable
[System.Runtime.InteropServices.Guid("496B0ABE-CDEE-11d3-88E8-00902754C43A")]
public interface IEnumerable
[System.Runtime.InteropServices.Guid("496B0ABE-CDEE-11d3-88E8-00902754C43A")]
[System.Runtime.InteropServices.ComVisible(true)]
public interface IEnumerable
type IEnumerable = interface
[<System.Runtime.InteropServices.Guid("496B0ABE-CDEE-11d3-88E8-00902754C43A")>]
type IEnumerable = interface
[<System.Runtime.InteropServices.Guid("496B0ABE-CDEE-11d3-88E8-00902754C43A")>]
[<System.Runtime.InteropServices.ComVisible(true)>]
type IEnumerable = interface
Public Interface IEnumerable
파생
특성

예제

다음 코드 예제에서는 및 인터페이스를 구현 하 여 사용자 지정 컬렉션을 반복 하는 모범 사례를 보여 줍니다 IEnumerable IEnumerator .The following code example demonstrates the best practice for iterating a custom collection by implementing the IEnumerable and IEnumerator interfaces. 이 예제에서는 이러한 인터페이스의 멤버를 명시적으로 호출 하지는 않지만 foreach (Visual Basic)를 사용 하 여 컬렉션을 반복할 수 있도록 구현 됩니다 For Each .In this example, members of these interfaces are not explicitly called, but they are implemented to support the use of foreach (For Each in Visual Basic) to iterate through the collection. 이 예제는 전체 콘솔 앱입니다.This example is a complete Console app. Visual Basic 앱을 컴파일하려면 프로젝트의 속성 페이지에서 시작 개체Sub Main 로 변경 합니다.To compile the Visual Basic app, change the Startup object to Sub Main in the project's Properties page.

인터페이스를 구현 하는 방법을 보여 주는 샘플은 IEnumerable 컬렉션 클래스에서 IEnumerable 인터페이스 구현 을 참조 하세요.For a sample that shows how to implement the IEnumerable interface, see Implementing the IEnumerable Interface in a Collection Class

using System;
using System.Collections;

// Simple business object.
public class Person
{
    public Person(string fName, string lName)
    {
        this.firstName = fName;
        this.lastName = lName;
    }

    public string firstName;
    public string lastName;
}

// Collection of Person objects. This class
// implements IEnumerable so that it can be used
// with ForEach syntax.
public class People : IEnumerable
{
    private Person[] _people;
    public People(Person[] pArray)
    {
        _people = new Person[pArray.Length];

        for (int i = 0; i < pArray.Length; i++)
        {
            _people[i] = pArray[i];
        }
    }

// Implementation for the GetEnumerator method.
    IEnumerator IEnumerable.GetEnumerator()
    {
       return (IEnumerator) GetEnumerator();
    }

    public PeopleEnum GetEnumerator()
    {
        return new PeopleEnum(_people);
    }
}

// When you implement IEnumerable, you must also implement IEnumerator.
public class PeopleEnum : IEnumerator
{
    public Person[] _people;

    // Enumerators are positioned before the first element
    // until the first MoveNext() call.
    int position = -1;

    public PeopleEnum(Person[] list)
    {
        _people = list;
    }

    public bool MoveNext()
    {
        position++;
        return (position < _people.Length);
    }

    public void Reset()
    {
        position = -1;
    }

    object IEnumerator.Current
    {
        get
        {
            return Current;
        }
    }

    public Person Current
    {
        get
        {
            try
            {
                return _people[position];
            }
            catch (IndexOutOfRangeException)
            {
                throw new InvalidOperationException();
            }
        }
    }
}

class App
{
    static void Main()
    {
        Person[] peopleArray = new Person[3]
        {
            new Person("John", "Smith"),
            new Person("Jim", "Johnson"),
            new Person("Sue", "Rabon"),
        };

        People peopleList = new People(peopleArray);
        foreach (Person p in peopleList)
            Console.WriteLine(p.firstName + " " + p.lastName);
    }
}

/* This code produces output similar to the following:
 *
 * John Smith
 * Jim Johnson
 * Sue Rabon
 *
 */
Imports System.Collections

' Simple business object.
Public Class Person

    Public Sub New(ByVal fName As String, ByVal lName As String)
        Me.firstName = fName
        Me.lastName = lName
    End Sub


    Public firstName As String
    Public lastName As String
End Class

' Collection of Person objects, which implements IEnumerable so that
' it can be used with ForEach syntax.
Public Class People
    Implements IEnumerable

    Private _people() As Person

    Public Sub New(ByVal pArray() As Person)
        _people = New Person(pArray.Length - 1) {}

        Dim i As Integer
        For i = 0 To pArray.Length - 1
            _people(i) = pArray(i)
        Next i
    End Sub

    ' Implementation of GetEnumerator.
    Public Function GetEnumerator() As IEnumerator _
      Implements IEnumerable.GetEnumerator

        Return New PeopleEnum(_people)
    End Function

End Class

' When you implement IEnumerable, you must also implement IEnumerator.
Public Class PeopleEnum
    Implements IEnumerator

    Public _people() As Person

    ' Enumerators are positioned before the first element
    ' until the first MoveNext() call.
    Dim position As Integer = -1

    Public Sub New(ByVal list() As Person)
        _people = list
    End Sub

    Public Function MoveNext() As Boolean Implements IEnumerator.MoveNext
        position = position + 1
        Return (position < _people.Length)
    End Function

    Public Sub Reset() Implements IEnumerator.Reset
        position = -1
    End Sub

    Public ReadOnly Property Current() As Object Implements IEnumerator.Current
        Get
            Try
                Return _people(position)
            Catch ex As IndexOutOfRangeException
                Throw New InvalidOperationException()
            End Try
        End Get
    End Property
End Class

Class App
    Shared Sub Main()
        Dim peopleArray() As Person = { _
            New Person("John", "Smith"), _
            New Person("Jim", "Johnson"), _
            New Person("Sue", "Rabon")}

        Dim peopleList As New People(peopleArray)
        Dim p As Person
        For Each p In peopleList
            Console.WriteLine(p.firstName + " " + p.lastName)
        Next

    End Sub
End Class

' This code produces output similar to the following:
' 
' John Smith
' Jim Johnson
' Sue Rabon

설명

IEnumerable 는 열거할 수 있는 제네릭이 아닌 모든 컬렉션에 대 한 기본 인터페이스입니다.IEnumerable is the base interface for all non-generic collections that can be enumerated. 이 인터페이스의 제네릭 버전은를 참조 하십시오 System.Collections.Generic.IEnumerable<T> .For the generic version of this interface see System.Collections.Generic.IEnumerable<T>. IEnumerable 단일 메서드인를 포함 합니다 .이 메서드는를 GetEnumerator 반환 IEnumerator 합니다.IEnumerable contains a single method, GetEnumerator, which returns an IEnumerator. IEnumeratorCurrent속성과 및 메서드를 노출 하 여 컬렉션을 반복 하는 기능을 제공 합니다 MoveNext Reset .IEnumerator provides the ability to iterate through the collection by exposing a Current property and MoveNext and Reset methods.

IEnumerable컬렉션 클래스에서 및를 구현 하 여 IEnumerator (Visual Basic) 구문을 사용 하도록 설정 하는 것이 가장 좋습니다 foreach For Each . 그러나 구현은 IEnumerable 필요 하지 않습니다.It is a best practice to implement IEnumerable and IEnumerator on your collection classes to enable the foreach (For Each in Visual Basic) syntax, however implementing IEnumerable is not required. 컬렉션에서를 구현 하지 않는 경우 IEnumerable GetEnumerator 인터페이스, 클래스 또는 구조체를 반환 하는 메서드를 제공 하 여이 구문을 지원 하려면 반복기 패턴을 따라야 합니다.If your collection does not implement IEnumerable, you must still follow the iterator pattern to support this syntax by providing a GetEnumerator method that returns an interface, class or struct. Visual Basic를 사용 하는 경우에 IEnumerator 의해 반환 되는 구현을 제공 해야 합니다 GetEnumerator .When using Visual Basic, you must provide an IEnumerator implementation, which is returned by GetEnumerator. C #을 사용 하 여 개발 하는 경우에 설명 된 대로 속성 및 및 메서드를 포함 하는 클래스를 제공 해야 Current MoveNext Reset IEnumerator 하지만 클래스는를 구현할 필요가 없습니다 IEnumerator .When developing with C# you must provide a class that contains a Current property, and MoveNext and Reset methods as described by IEnumerator, but the class does not have to implement IEnumerator.

메서드

GetEnumerator()

컬렉션을 반복하는 열거자를 반환합니다.Returns an enumerator that iterates through a collection.

확장 메서드

Cast<TResult>(IEnumerable)

IEnumerable의 요소를 지정된 형식으로 캐스팅합니다.Casts the elements of an IEnumerable to the specified type.

OfType<TResult>(IEnumerable)

지정된 형식에 따라 IEnumerable의 요소를 필터링합니다.Filters the elements of an IEnumerable based on a specified type.

AsParallel(IEnumerable)

쿼리를 병렬화할 수 있도록 합니다.Enables parallelization of a query.

AsQueryable(IEnumerable)

IEnumerableIQueryable로 변환합니다.Converts an IEnumerable to an IQueryable.

적용 대상

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