Enum.Equals(Object) 方法

定义

命名空间:

System

程序集:

netstandard.dll, System.Runtime.dll

Source:

Enum.cs

返回一个值，该值指示此实例是否等于指定的对象。

C#

public override bool Equals(object? obj);

参数

obj

Object

与此实例进行比较的对象，或为 null。

返回

Boolean

如果枚举值 obj 的类型和基础值与此实例相同，则为 true；否则为 false。

示例

下面的示例演示 Equals 方法的用法。

C#

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

以下示例定义两种枚举类型： SledDog 和 WorkDog。 枚举 SledDog 具有两个具有相同基础值的成员 SledDog.AlaskanMalamute 和 SledDog.Malamute。 对 方法的 Equals 调用指示这些值相等，因为它们的基础值相同。 SledDog.Malamute和 WorkDog.Newfoundland 成员具有相同的基础值，尽管它们表示不同的枚举类型。 调用 Equals 方法表示这些值不相等。

C#

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

注解

方法 Enum.Equals(Object) 重写 ValueType.Equals(Object) 以定义如何计算枚举成员的相等性。

适用于

另请参阅

• CompareTo(Object)