FlagsAttributes in C#

 Introduction

    In C# enum is a named integer constant. But a type can have only one enum value. FlagsAttribute is used to assign multiple enum values.

Example

using System;

public class Program

{

public static void Main()

{

var rocky = new Person("Rock", Vehicle.BMWX5);

var peter = new Person("Peter Parker", Vehicle.Highlander);

rocky.PersonInfo();

            //Output: Rock owns BMWX5

peter.PersonInfo();

            //Output: Peter Parker owns Highlander

}

}

public class Person

{

public string Name{get;set;}

public Vehicle Vehicle{get;set;}

public Person(string name, Vehicle vehicle)

{

Name = name;

Vehicle=vehicle;

}

public void PersonInfo()

{

Console.WriteLine($"{Name} owns {Vehicle}");

}

}

public enum Vehicle

{

none=0,

BMWX5=1,

LandRover=2,

LincolnAviator=4,

Highlander=8

}

In the above program, one person can own one vehicle.

What if a person owns 2 or more vehicles. In this case FlagsAttribute is useful.

using System;

public class Program

{

public static void Main()

{

                //vehicle2 is now represents 2 vehicles BMWX5 and Highlander both.

var vehicle2 = Vehicle.BMWX5|Vehicle.Highlander;

     var rocky = new Person("Rock", Vehicle.BMWX5);

var peter = new Person("Peter Parker", Vehicle.Highlander);

                // John owns vehicle2 means he has 2 vehicles.

var john = new Person("John", vehicle2);

rocky.PersonInfo();

peter.PersonInfo();

john.PersonInfo();

                //Output: John owns BMWX5, Highlander

}

}

public class Person

{

public string Name{get;set;}

public Vehicle Vehicle{get;set;}

public Person(string name, Vehicle vehicle)

{

Name = name;

Vehicle=vehicle;

}

public void PersonInfo()

{

Console.WriteLine($"{Name} owns {Vehicle}");

}

}

[Flags]

public enum Vehicle

{

none=0,

BMWX5=1,

LandRover=2,

LincolnAviator=4,

Highlander=8

}  

Complete Code