Enum ToString with user friendly strings

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My enum consists of the following values:

private enum PublishStatusses{
    NotCompleted,
    Completed,
    Error
};

I want to be able to output these values in a user friendly way though.
I don't need to be able to go from string to value again.

24 Answers

I use the Description attribute from the System.ComponentModel namespace. Simply decorate the enum:

private enum PublishStatusValue
{
    [Description("Not Completed")]
    NotCompleted,
    Completed,
    Error
};

Then use this code to retrieve it:

public static string GetDescription<T>(this T enumerationValue)
    where T : struct
{
    Type type = enumerationValue.GetType();
    if (!type.IsEnum)
    {
        throw new ArgumentException("EnumerationValue must be of Enum type", "enumerationValue");
    }

    //Tries to find a DescriptionAttribute for a potential friendly name
    //for the enum
    MemberInfo[] memberInfo = type.GetMember(enumerationValue.ToString());
    if (memberInfo != null && memberInfo.Length > 0)
    {
        object[] attrs = memberInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false);

        if (attrs != null && attrs.Length > 0)
        {
            //Pull out the description value
            return ((DescriptionAttribute)attrs[0]).Description;
        }
    }
    //If we have no description attribute, just return the ToString of the enum
    return enumerationValue.ToString();
}

I do this with extension methods:

public enum ErrorLevel
{
  None,
  Low,
  High,
  SoylentGreen
}

public static class ErrorLevelExtensions
{
  public static string ToFriendlyString(this ErrorLevel me)
  {
    switch(me)
    {
      case ErrorLevel.None:
        return "Everything is OK";
      case ErrorLevel.Low:
        return "SNAFU, if you know what I mean.";
      case ErrorLevel.High:
        return "Reaching TARFU levels";
      case ErrorLevel.SoylentGreen:
        return "ITS PEOPLE!!!!";
      default:
        return "Get your damn dirty hands off me you FILTHY APE!";
    }
  }
}

Maybe I'm missing something, but what's wrong with Enum.GetName?

public string GetName(PublishStatusses value)
{
    return Enum.GetName(typeof(PublishStatusses), value)
}

edit: for user-friendly strings, you need to go through a .resource to get internationalisation/localisation done, and it would arguably be better to use a fixed key based on the enum key than a decorator attribute on the same.

The easiest solution here is to use a custom extension method (in .NET 3.5 at least - you can just convert it into a static helper method for earlier framework versions).

public static string ToCustomString(this PublishStatusses value)
{
    switch(value)
    {
        // Return string depending on value.
    }
    return null;
}

I am assuming here that you want to return something other than the actual name of the enum value (which you can get by simply calling ToString).

That other post is Java. You can't put methods in Enums in C#.

just do something like this:

PublishStatusses status = ...
String s = status.ToString();

If you want to use different display values for your enum values, you could use Attributes and Reflection.

With respect to Ray Booysen, there is a bug in the code: Enum ToString with user friendly strings

You need to account for multiple attributes on the enum values.

public static string GetDescription<T>(this object enumerationValue)
            where T : struct
    {
        Type type = enumerationValue.GetType();
        if (!type.IsEnum)
        {
            throw new ArgumentException("EnumerationValue must be of Enum type", "enumerationValue");
        }

        //Tries to find a DescriptionAttribute for a potential friendly name
        //for the enum
        MemberInfo[] memberInfo = type.GetMember(enumerationValue.ToString());
        if (memberInfo != null && memberInfo.Length > 0)
        {
            object[] attrs = memberInfo[0].GetCustomAttributes(typeof(DescriptionAttribute), false);

            if (attrs != null && attrs.Length > 0 && attrs.Where(t => t.GetType() == typeof(DescriptionAttribute)).FirstOrDefault() != null)
            {
                //Pull out the description value
                return ((DescriptionAttribute)attrs.Where(t=>t.GetType() == typeof(DescriptionAttribute)).FirstOrDefault()).Description;
            }
        }
        //If we have no description attribute, just return the ToString of the enum
        return enumerationValue.ToString();

Instead of using an enum use a static class.

replace

private enum PublishStatuses{
    NotCompleted,
    Completed,
    Error
};

with

private static class PublishStatuses{
    public static readonly string NotCompleted = "Not Completed";
    public static readonly string Completed = "Completed";
    public static readonly string Error = "Error";
};

it will be used like this

PublishStatuses.NotCompleted; // "Not Completed"

Issue using the top "extension method" solutions:

A private enum is often used inside another class. The extension method solution is not valid there since it must be in it's own class. This solution can be private and embedded in another class.

Use Enum.GetName

From the above link...

using System;

public class GetNameTest {
    enum Colors { Red, Green, Blue, Yellow };
    enum Styles { Plaid, Striped, Tartan, Corduroy };

    public static void Main() {

        Console.WriteLine("The 4th value of the Colors Enum is {0}", Enum.GetName(typeof(Colors), 3));
        Console.WriteLine("The 4th value of the Styles Enum is {0}", Enum.GetName(typeof(Styles), 3));
    }
}
// The example displays the following output:
//       The 4th value of the Colors Enum is Yellow
//       The 4th value of the Styles Enum is Corduroy

In case you just want to add a whitespace between the words, it is as simple as

string res = Regex.Replace(PublishStatusses.NotCompleted, "[A-Z]", " $0").Trim();

I'm 7 years late for the party :-) But I'm sure this topic is visited frequently.
So I wanted to add a little sugar to the coffee:

What about the "F" format string specifier?

PublishStatusses[] ps = Enum.GetValues<PublishStatusses>();
ps.ToList().ForEach(c => Console.Write($"{c:F} "));

There is no need for any explicit function call.

In fact there isn't even need for any format specifier. In case of a variable assignment to a string, ToString() does the work:

string foo = PublishStatusses.Error.ToString(); // or ToString("F")

And if it is about to insert spaces between words of a CamelCase string, you can just use a regular expression:

Regex.Replace(foo, "(\\B[A-Z])", " $1")

I use a generic class to store the enum/description pairs and a nested helper class to get the description.

The enum:

enum Status { Success, Fail, Pending }

The generic class:

Note: Since a generic class cannot be constrained by an enum I am constraining by struct instead and checking for enum in the constructor.

public class EnumX<T> where T : struct
{
    public T Code { get; set; }
    public string Description { get; set; }

    public EnumX(T code, string desc)
    {
        if (!typeof(T).IsEnum) throw new NotImplementedException();

        Code = code;
        Description = desc;
    }

    public class Helper
    {
        private List<EnumX<T>> codes;

        public Helper(List<EnumX<T>> codes)
        {
            this.codes = codes;
        }

        public string GetDescription(T code)
        {
            EnumX<T> e = codes.Where(c => c.Code.Equals(code)).FirstOrDefault();
            return e is null ? "Undefined" : e.Description;
        }
    }
}

Usage:

EnumX<Status>.Helper StatusCodes = new EnumX<Status>.Helper(new List<EnumX<Status>>()
        {
            new EnumX<Status>(Status.Success,"Operation was successful"),
            new EnumX<Status>(Status.Fail,"Operation failed"),
            new EnumX<Status>(Status.Pending,"Operation not complete. Please wait...")
        });

        Console.WriteLine(StatusCodes.GetDescription(Status.Pending));
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