Enum.Equals(Object) Enum.Equals(Object) Enum.Equals(Object) Enum.Equals(Object) Method

Definizione

Restituisce un valore che indica se questa istanza è uguale a un oggetto specificato.Returns a value indicating whether this instance is equal to a specified object.

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

Parametri

obj
Object Object Object Object

Oggetto da confrontare con questa istanza o null.An object to compare with this instance, or null.

Restituisce

true se obj è un valore di enumerazione dello stesso tipo e con lo stesso valore sottostante dell'istanza; in caso contrario, false.true if obj is an enumeration value of the same type and with the same underlying value as this instance; otherwise, false.

Esempi

Nell'esempio riportato di seguito viene illustrato l'utilizzo del metodo Equals.The following example illustrates the use of the Equals method.

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
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

Nell'esempio seguente vengono definiti due tipi di SledDog enumerazione WorkDog, e.The following example defines two enumeration types, SledDog and WorkDog. L' SledDog enumerazione ha due membri, SledDog.AlaskanMalamute e SledDog.Malamute, che hanno lo stesso valore sottostante.The SledDog enumeration has two members, SledDog.AlaskanMalamute and SledDog.Malamute, that have the same underlying value. La chiamata al Equals metodo indica che questi valori sono uguali perché i valori sottostanti sono uguali.The call to the Equals method indicates that these values are equal because their underlying values are the same. I SledDog.Malamute membri WorkDog.Newfoundland e hanno lo stesso valore sottostante, sebbene rappresentino tipi di enumerazione diversi.The SledDog.Malamute and WorkDog.Newfoundland members have the same underlying value, although they represent different enumeration types. Una chiamata al Equals metodo indica che questi valori non sono uguali.A call to the Equals method indicates that these values are not equal.

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
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

Commenti

Il Enum.Equals(Object) metodo esegue ValueType.Equals(Object) l'override di per definire come vengono valutati i membri dell'enumerazione per verificare l'uguaglianza.The Enum.Equals(Object) method overrides ValueType.Equals(Object) to define how enumeration members are evaluated for equality.

Si applica a

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