System.Enum.IsDefined 方法例子

然后，它使用通过设置多个位字段而生成的可能基础枚举值、字符串名称和组合值来调用 IsDefined 方法。

using System;

[Flags] public enum PetType

{

None = 0, Dog = 1, Cat = 2, Rodent = 4, Bird = 8, Reptile = 16, Other = 32

};

public class Example

{

public static void Main()

{

object value;

// Call IsDefined with underlying integral value of member.

value = 1;

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

// Call IsDefined with invalid underlying integral value.

value = 64;

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

// Call IsDefined with string containing member name.

value = "Rodent";

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

// Call IsDefined with a variable of type PetType.

value = PetType.Dog;

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

value = PetType.Dog | PetType.Cat;

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

// Call IsDefined with uppercase member name.

value = "None";

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

value = "NONE";

Console.WriteLine("{0}: {1}", value, Enum.IsDefined(typeof(PetType), value));

// Call IsDefined with combined value

value = PetType.Dog | PetType.Bird;

Console.WriteLine("{0:D}: {1}", value, Enum.IsDefined(typeof(PetType), value));

value = value.ToString();

Console.WriteLine("{0:D}: {1}", value, Enum.IsDefined(typeof(PetType), value));

}

}

// The example displays the following output:

// 1: True

// 64: False

// Rodent: True

// Dog: True

// Dog, Cat: False

// None: True

// NONE: False

// 9: False

// Dog, Bird: False