c# – Create a variable that can only hold a fixed set of values (aka an Enum Constant)

A enum constant is a special kind of variable that can only take a set number of values, e.g.:

[csharp]
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp
{
class EnumConstantDemo
{
// notice that you have to place this outside the method, othewise the method
// wont recognise this a enum constant (aka variable type)
enum Colour
{
red,
green,
blue // notice no comma for the last one.
}

static void Main(string[] args)
{

Colour Favourite = Colour.green;

switch (Favourite)
{
case Colour.green:
Console.WriteLine("Your fave colour is green");
break;
case Colour.red:
Console.WriteLine("Your fave colour is red");
break;
case Colour.blue:
Console.WriteLine("Your fave colour is blue");
break;
default:
Console.WriteLine("Sorry don’t know your fave colour");
break;
}

Console.WriteLine("Switch statement has ended");
}
}
}

[/csharp]

The cool thing about this aproach is that VS2013 will recognise the enum constant as type of variable, and hence will offer intellisense, e.g.: