using System;

[Flags] // should be on enums used as bit flags

public enum E

{

    // powers of two !

    A = 8, // 1 0 0 0

    B = 4, // 0 1 0 0

    C = 2, // 0 0 1 0

    D = 1, // 0 0 0 1

    None=0,// 0 0 0 0

}       

​

public class Program

{

    public static void Main()

    {

        E v = E.A | E.B; // |: bitwise or, add a value to the bitflag

        Console.WriteLine("A and B:" + v);

        v = v | E.C; // |: bitwise or, add a value to the bitflag

        Console.WriteLine("Added C : " + v);

        v = v ^ E.B; // ^: bitwise xor, remove a value to the bitflag

        Console.WriteLine("Removed B:" + v);

        Console.WriteLine("Has A ? {0} {1}", ((v & E.A) == E.A), v.HasFlag(E.A)); // HasFlag(x) is equivalent to v & x == x

        Console.WriteLine("Has B ? " + ((v & E.B) == E.B));

        Console.WriteLine("Has C ? " + ((v & E.C) == E.C));

        EnumTest et = new EnumTest();

        Console.WriteLine(et.E);

        et.C = true;

        Console.WriteLine(et.E);

        et.D = true;

        Console.WriteLine(et.E);

    }

}

​

public class EnumTest

{

    private E _e; // actual value

    public E E { get { return _e; } } // for demo

    // booleans properties for binding that actually add or remove enum value to the enum _e

    public bool A { get { return _e.HasFlag(E.A); } set { _e = _e | E.A; } }

    public bool B { get { return _e.HasFlag(E.B); } set { _e = _e | E.B; } }

    public bool C { get { return _e.HasFlag(E.C); } set { _e = _e | E.C; } }

    public bool D { get { return _e.HasFlag(E.D); } set { _e = _e | E.D; } }

}