enum_3.cs

    // Add the attribute Flags or FlagsAttribute.
    [Flags]
    public enum CarOptions
    {
        // The flag for SunRoof is 0001.
        SunRoof = 0x01,
        // The flag for Spoiler is 0010.
        Spoiler = 0x02,
        // The flag for FogLights is 0100.
        FogLights = 0x04,
        // The flag for TintedWindows is 1000.
        TintedWindows = 0x08,
    }

    class FlagTest
    {
        static void Main()
        {
            // The bitwise OR of 0001 and 0100 is 0101.
            CarOptions options = CarOptions.SunRoof | CarOptions.FogLights;

            // Because the Flags attribute is specified, Console.WriteLine displays
            // the name of each enum element that corresponds to a flag that has
            // the value 1 in variable options.
            Console.WriteLine(options);
            // The integer value of 0101 is 5.
            Console.WriteLine((int)options);
        }
    }
    /* Output:
       SunRoof, FogLights
       5
    */