Enum.Equals(Object) メソッド

定義

このインスタンスが指定されたオブジェクトに等しいかどうかを示す値を返します。

public:
 override bool Equals(System::Object ^ obj);
public override bool Equals (object obj);
public override bool Equals (object? obj);
override this.Equals : obj -> bool
Public Overrides Function Equals (obj As Object) As Boolean

パラメーター

obj
Object

対象のインスタンスと比較する対象のオブジェクト、または null

戻り値

obj が同じ型の列挙体値で、基になる値がこのインスタンスと同じである場合は true、それ以外の場合は false です。

Equals メソッドの使用例を次に示します。

using namespace System;
public enum class Colors
{
   Red, Green, Blue, Yellow
};

public enum class Mammals
{
   Cat, Dog, Horse, Dolphin
};

int main()
{
   Mammals myPet = Mammals::Cat;
   Colors myColor = Colors::Red;
   Mammals yourPet = Mammals::Dog;
   Colors yourColor = Colors::Red;
   Console::WriteLine(  "My favorite animal is a {0}", myPet );
   Console::WriteLine(  "Your favorite animal is a {0}", yourPet );
   Console::WriteLine(  "Do we like the same animal? {0}", myPet.Equals( yourPet ) ? (String^)"Yes" : "No" );
   Console::WriteLine();
   Console::WriteLine(  "My favorite color is {0}", myColor );
   Console::WriteLine(  "Your favorite color is {0}", yourColor );
   Console::WriteLine(  "Do we like the same color? {0}", myColor.Equals( yourColor ) ? (String^)"Yes" : "No" );
   Console::WriteLine();
   Console::WriteLine(  "The value of my color ({0}) is {1}", myColor, Enum::Format( Colors::typeid, myColor,  "d" ) );
   Console::WriteLine(  "The value of my pet (a {0}) is {1}", myPet, Enum::Format( Mammals::typeid, myPet,  "d" ) );
   Console::WriteLine(  "Even though they have the same value, are they equal? {0}", myColor.Equals( myPet ) ? (String^)"Yes" : "No" );
}
// The example displays the following output:
//    My favorite animal is a Cat
//    Your favorite animal is a Dog
//    Do we like the same animal? No
//    
//    My favorite color is Red
//    Your favorite color is Red
//    Do we like the same color? Yes
//    
//    The value of my color (Red) is 0
//    The value of my pet (a Cat) is 0
//    Even though they have the same value, are they equal? No
using System;

public class EqualsTest {
    enum Colors { Red, Green, Blue, Yellow };
    enum Mammals { Cat, Dog, Horse, Dolphin };

    public static void Main() {
        Mammals myPet = Mammals.Cat;
        Colors myColor = Colors.Red;
        Mammals yourPet = Mammals.Dog;
        Colors yourColor = Colors.Red;

        Console.WriteLine("My favorite animal is a {0}", myPet);
        Console.WriteLine("Your favorite animal is a {0}", yourPet);
        Console.WriteLine("Do we like the same animal? {0}", myPet.Equals(yourPet) ? "Yes" : "No");

        Console.WriteLine();
        Console.WriteLine("My favorite color is {0}", myColor);
        Console.WriteLine("Your favorite color is {0}", yourColor);
        Console.WriteLine("Do we like the same color? {0}", myColor.Equals(yourColor) ? "Yes" : "No");

        Console.WriteLine();
        Console.WriteLine("The value of my color ({0}) is {1}", myColor, Enum.Format(typeof(Colors), myColor, "d"));
        Console.WriteLine("The value of my pet (a {0}) is {1}", myPet, Enum.Format(typeof(Mammals), myPet, "d"));
        Console.WriteLine("Even though they have the same value, are they equal? {0}",
                    myColor.Equals(myPet) ? "Yes" : "No");
    }
}
// The example displays the following output:
//    My favorite animal is a Cat
//    Your favorite animal is a Dog
//    Do we like the same animal? No
//
//    My favorite color is Red
//    Your favorite color is Red
//    Do we like the same color? Yes
//
//    The value of my color (Red) is 0
//    The value of my pet (a Cat) is 0
//    Even though they have the same value, are they equal? No
open System

type Colors =
    | Red = 0
    | Green = 1
    | Blue = 2
    | Yellow = 3

type Mammals =
    | Cat = 0
    | Dog = 1
    | Horse = 2
    | Dolphin = 3

let myPet = Mammals.Cat
let myColor = Colors.Red
let yourPet = Mammals.Dog
let yourColor = Colors.Red

printfn 
    $"""My favorite animal is a {myPet}
Your favorite animal is a {yourPet}
Do we like the same animal? {if myPet.Equals yourPet then "Yes" else "No"}

My favorite color is {myColor}
Your favorite color is {yourColor}
Do we like the same color? {if myColor.Equals yourColor then "Yes" else "No"}

The value of my color ({myColor}) is {Enum.Format(typeof<Colors>, myColor, "d")}
The value of my pet (a {myPet}) is {Enum.Format(typeof<Mammals>, myPet, "d")}
Even though they have the same value, are they equal? {if myColor.Equals myPet then "Yes" else "No"}"""

// The example displays the following output:
//    My favorite animal is a Cat
//    Your favorite animal is a Dog
//    Do we like the same animal? No
//
//    My favorite color is Red
//    Your favorite color is Red
//    Do we like the same color? Yes
//
//    The value of my color (Red) is 0
//    The value of my pet (a Cat) is 0
//    Even though they have the same value, are they equal? No
Public Class EqualsTest
    Enum Colors
        Red
        Green
        Blue
        Yellow
    End Enum 
    
    Enum Mammals
        Cat
        Dog
        Horse
        Dolphin
    End Enum 
    
    Public Shared Sub Main()
        Dim myPet As Mammals = Mammals.Cat
        Dim myColor As Colors = Colors.Red
        Dim yourPet As Mammals = Mammals.Dog
        Dim yourColor As Colors = Colors.Red
        Dim output as string
        
        Console.WriteLine("My favorite animal is a {0}", myPet)
        Console.WriteLine("Your favorite animal is a {0}", yourPet)
        If myPet.Equals(yourPet) Then output = "Yes" Else output = "No"
        Console.WriteLine("Do we like the same animal? {0}", output)
        
        Console.WriteLine()
        Console.WriteLine("My favorite color is {0}", myColor)
        Console.WriteLine("Your favorite color is {0}", yourColor)
        If myColor.Equals(yourColor) Then output = "Yes" Else output = "No"
        Console.WriteLine("Do we like the same color? {0}", output)
        
        Console.WriteLine()
        Console.WriteLine("The value of my color ({0}) is {1}", myColor, [Enum].Format(GetType(Colors), myColor, "d"))
        Console.WriteLine("The value of my pet (a {0}) is {1}", myPet, [Enum].Format(GetType(Mammals), myPet, "d"))
        Console.WriteLine("Even though they have the same value, are they equal? {0}", 
                          If(myColor.Equals(myPet), "Yes", "No"))
    End Sub 
End Class 
' The example displays the following output:
'    My favorite animal is a Cat
'    Your favorite animal is a Dog
'    Do we like the same animal? No
'    
'    My favorite color is Red
'    Your favorite color is Red
'    Do we like the same color? Yes
'    
'    The value of my color (Red) is 0
'    The value of my pet (a Cat) is 0
'    Even though they have the same value, are they equal? No

次の例では、SledDogWorkDogという 2 つの列挙型を定義しています。 SledDog列挙体には、SledDog.AlaskanMalamuteSledDog.Malamuteという 2 つのメンバーがあり、基になる値が同じです。 Equalsメソッドの呼び出しは、基になる値が同じであるため、これらの値が等しいことを示しています。 SledDog.MalamuteメンバーとWorkDog.Newfoundlandメンバーは、基になる値が同じですが、異なる列挙型を表しています。 Equalsメソッドの呼び出しは、これらの値が等しくないことを示します。

using System;

public enum SledDog { Unknown=0, AlaskanMalamute=1, Malamute=1,
                      Husky=2, SiberianHusky=2 };

public enum WorkDog { Unknown=0, Newfoundland=1, GreatPyrennes=2 };

public class Example
{
   public static void Main()
   {
      SledDog dog1 = SledDog.Malamute;
      SledDog dog2 = SledDog.AlaskanMalamute;
      WorkDog dog3 = WorkDog.Newfoundland;

      Console.WriteLine("{0:F} ({0:D}) = {1:F} ({1:D}): {2}",
                        dog1, dog2, dog1.Equals(dog2));
      Console.WriteLine("{0:F} ({0:D}) = {1:F} ({1:D}): {2}",
                        dog1, dog3, dog1.Equals(dog3));
   }
}
// The example displays the following output:
//       Malamute (1) = Malamute (1): True
//       Malamute (1) = Newfoundland (1): False
type SledDog =
    | Unknown = 0
    | AlaskanMalamute = 1
    | Malamute = 1
    | Husky = 2
    | SiberianHusky = 2

type WorkDog =
    | Unknown = 0
    | Newfoundland = 1
    | GreatPyrennes = 2

let dog1 = SledDog.Malamute
let dog2 = SledDog.AlaskanMalamute
let dog3 = WorkDog.Newfoundland

printfn $"{dog1:F} ({dog1:D}) = {dog2:F} ({dog2:D}): {dog1.Equals dog2}"
printfn $"{dog1:F} ({dog1:D}) = {dog3:F} ({dog3:D}): {dog1.Equals dog3}"
// The example displays the following output:
//       Malamute (1) = Malamute (1): True
//       Malamute (1) = Newfoundland (1): False
Public Enum SledDog As Integer
   Unknown=0
   AlaskanMalamute=1
   Malamute=1
   Husky=2
   SiberianHusky=2
End Enum

Public Enum WorkDog As Integer
   Unknown=0
   Newfoundland=1
   GreatPyrennes=2
End Enum

Module Example
   Public Sub Main()
      Dim dog1 As SledDog = SledDog.Malamute
      Dim dog2 As SledDog = SledDog.AlaskanMalamute
      Dim dog3 As WorkDog = WorkDog.Newfoundland
      
      Console.WriteLine("{0:F} ({0:D}) = {1:F} ({1:D}): {2}", 
                        dog1, dog2, dog1.Equals(dog2))
      Console.WriteLine("{0:F} ({0:D}) = {1:F} ({1:D}): {2}",
                        dog1, dog3, dog1.Equals(dog3))
   End Sub
End Module
' The example displays the following output:
'       Malamute (1) = Malamute (1): True
'       Malamute (1) = Newfoundland (1): False

注釈

Enum.Equals(Object)メソッドは、列挙メンバーが等しいかどうかを評価する方法を定義するためにValueType.Equals(Object)をオーバーライドします。

適用対象

こちらもご覧ください