ObjectEnum 1.0.0

.NET Standard 2.0
dotnet add package ObjectEnum --version 1.0.0
NuGet\Install-Package ObjectEnum -Version 1.0.0
This command is intended to be used within the Package Manager Console in Visual Studio, as it uses the NuGet module's version of Install-Package.
<PackageReference Include="ObjectEnum" Version="1.0.0" />
For projects that support PackageReference, copy this XML node into the project file to reference the package.
paket add ObjectEnum --version 1.0.0
#r "nuget: ObjectEnum, 1.0.0"
#r directive can be used in F# Interactive, C# scripting and .NET Interactive. Copy this into the interactive tool or source code of the script to reference the package.
// Install ObjectEnum as a Cake Addin
#addin nuget:?package=ObjectEnum&version=1.0.0

// Install ObjectEnum as a Cake Tool
#tool nuget:?package=ObjectEnum&version=1.0.0

ObjectEnum

ObjectEnum is a wrapper for enums, adding a certain degree of polymorphism.

Examples

Restrict enum values to a subset

Conssider the WorkDay class:

public class WorkDay : ObjectEnum<DayOfWeek>
{
    public WorkDay(DayOfWeek value)
        : base(value) { }

    private static readonly DayOfWeek[] Values = new[]
    {
        DayOfWeek.Monday, DayOfWeek.Tuesday, DayOfWeek.Wednesday,
        DayOfWeek.Thursday, DayOfWeek.Friday
    };

    protected override IReadOnlyCollection<DayOfWeek> GetDefinedValues()
        => Values;
}

Which will produce the following results:

var sunday = new WorkDay(DayOfWeek.Sunday); //throws exception

var monday = new WorkDay(DayOfWeek.Monday); //works fine
var label = $"{monday} is day {(int)monday}." //produces: "Monday is day 1."
var mondayIsAlwaysMonday = monday == DayOfWeek.Monday; //true, sorry...

Inheritance

Conssider these classes:

public class ChillDay : ObjectEnum<DayOfWeek>
{
    public ChillDay(DayOfWeek value)
        : base(value) { }

    private static readonly DayOfWeek[] Values = new[]
    {
        DayOfWeek.Saturday, DayOfWeek.Sunday
    };

    protected override IReadOnlyCollection<DayOfWeek> GetDefinedValues()
        => Values;
}

public class FunDay : ChillDay
{
    public FunDay(DayOfWeek value)
        : base(value) { }

    private static readonly DayOfWeek[] Values = new[]
    {
        DayOfWeek.Saturday, DayOfWeek.Sunday, DayOfWeek.Friday
    };

    protected override IReadOnlyCollection<DayOfWeek> GetDefinedValues()
        => Values;
}

Which will produce the following results:

var sunday = new ChillDay(DayOfWeek.Sunday);
var funday = new FundDay(DayOfWeek.Sunday);

var sundayIsFunday = sunday == funday; //true

In this case the comparison will return true, because FundDay inherits ChillDay. However in the case of a Workday, this would not be the case as there is no relation between a WorkDay and a FundDay.

var friday = new WorkDay(DayOfWeek.Friday);
var funday = new FundDay(DayOfWeek.Friday);

var workFridayIsNoFunFriday = friday == funday; //false

Switch cases

You can easily use a ObjectEnum in a switch case, however you will need to cast it to the appropriate enum.

var friday = new WorkDay(DayOfWeek.Friday);

switch((DayOfWeek)friday){
    case DayOfWeek.Monday:
        //do something monday related
        break;
        /*...*/
    case DayOfWeek.Friday:
        //do something friday related
        break;
}

Or cast it to an integer.

var friday = new WorkDay(DayOfWeek.Friday);

switch((int)friday){
    case 1:
        //do something monday related
        break;
        /*...*/
    case 5:
        //do something friday related
        break;
}

Declaring your own ObjectEnums


//you can optionally declare an abstract base type for your implementations
public abstract class Size : ObjectEnum<Size.Value>
{
    //define a single enum containing all possible values
    //it can be a nested enum like it is here,
    //but this is not required
    public enum Value
    {
        Unknown = 0,
        ExtraSmall = 1,
        Small = 2,
        Medium = 3,
        Large = 4,
        ExtraLarge = 5
    }

    protected Size(Value value)
        : base(value) { }
}

public class BasicSize : Size
{
    public BasicSize(Value value)
        : base(value) { }

    //declaring a static Values array reduces
    //the overhead on creating a new array each time
    //we instantiate a BasicSize object
    private static readonly Value[] Values = new[]
    {
        Value.Unknown, Value.Small, Value.Medium, Value.Large
    };

    //override GetDefinedValues to restrict the possible values for BasicSize
    protected override IReadOnlyCollection<Value> GetDefinedValues()
        => Values;
}

//inherit BasicSize so we can compare the values
public class ExtendedSize : BasicSize
{
    public ExtendedSize(Value value)
        : base(value) { }

    //not the prefered way, but should work
    protected override IReadOnlyCollection<Value> GetDefinedValues()
        => new[] {
            Value.Unknown, Value.ExtraSmall, Value.Small, Value.Medium, Value.Large, Value.ExtraLarge
        };
}

Other helpful stuff

As you may have noticed, it is easy to cast between a ObjectEnum and its underlying enum Type, as well as casting to the int representation.

Besides this, a number of helper methods are defined to help you instantiate ObjectEnums

var isFriday = WorkDay.TryParse("Friday", out var friday); //returns true, friday = new WorkDay(DayOfWeek.Friday)
var isMonday = WorkDay.TryParse("monday", ignoreCase: false, out var mondaytues); //returns true, monday = new WorkDay(DayOfWeek.Monday)
var tuesday =  WorkDay.Parse<WorkDay>("tuesday"); //returns new WorkDay(DayOfWeek.Tuesday)
var wednessday = WorkDay.Create<WorkDay>(DayOfWeek.Wednessday);  //returns new WorkDay(DayOfWeek.Wednessday)

You can also use the various overloads of IsDefined to determine whether a certain value is valid for the given ObjectEnum.

Product Versions
.NET net5.0 net5.0-windows net6.0 net6.0-android net6.0-ios net6.0-maccatalyst net6.0-macos net6.0-tvos net6.0-windows net7.0 net7.0-android net7.0-ios net7.0-maccatalyst net7.0-macos net7.0-tvos net7.0-windows
.NET Core netcoreapp2.0 netcoreapp2.1 netcoreapp2.2 netcoreapp3.0 netcoreapp3.1
.NET Standard netstandard2.0 netstandard2.1
.NET Framework net461 net462 net463 net47 net471 net472 net48
MonoAndroid monoandroid
MonoMac monomac
MonoTouch monotouch
Tizen tizen40 tizen60
Xamarin.iOS xamarinios
Xamarin.Mac xamarinmac
Xamarin.TVOS xamarintvos
Xamarin.WatchOS xamarinwatchos
Compatible target framework(s)
Additional computed target framework(s)
Learn more about Target Frameworks and .NET Standard.
  • .NETStandard 2.0

    • No dependencies.

NuGet packages

This package is not used by any NuGet packages.

GitHub repositories

This package is not used by any popular GitHub repositories.

Version Downloads Last updated
1.0.0 403 11/15/2019
1.0.0-alpha1 297 10/15/2019
1.0.0-alpha 296 10/15/2019

Added compare operators

Please refer to the GitHub repo for documentation as well as any issues, comments  or requests.