C# Enum IsDefined

Description

Enum IsDefined returns an indication whether a constant with a specified value exists in a specified enumeration.

Syntax

Enum.IsDefined has the following syntax.

[ComVisibleAttribute(true)]/*w  w w. j av a2s .  c  o  m*/
public static bool IsDefined(
  Type enumType,
  Object value
)

Parameters

Enum.IsDefined has the following parameters.

• enumType - An enumeration type.
• value - The value or name of a constant in enumType.

Returns

Enum.IsDefined method returns true if a constant in enumType has a value equal to value; otherwise, false.

Example

The IsDefined method returns false when you pass it an enumeration value that has two bit fields set.

/*ww  w  .ja  v a 2s.  c om*/
using System;

[Flags]
public enum Pets
{
    None = 0, Dog = 1, Cat = 2, Bird = 4,
    Rodent = 8, Other = 16
};

public class Example
{
    public static void Main()
   {
      Pets value = Pets.Dog | Pets.Cat;
      Console.WriteLine(Pets.IsDefined(typeof(Pets), 1));
      string name = value.ToString();
      Console.WriteLine(Pets.IsDefined(typeof(Pets),2));
   }
}

The code above generates the following result.