Convert enum to string having a space

Question

I have an enum which I want to present as string using special way:

public enum FailureDescription
{
   MemoryFailure,
   Fragmentation,
   SegmentationFault
}

I want to print the value of that enum as following : FailureDescription.MemoryFailure.ToString() - > Memory Failure Can I do that ? How? Implement ToString?

As I know ToSttring working by default on enums.: http://msdn.microsoft.com/en-us/library/a0h36syw%28v=vs.110%29.aspx — Lóri Nóda, Jan 18 '15 at 13:42
See [this](http://stackoverflow.com/questions/773303/splitting-camelcase) answer. — Yuval Itzchakov, Jan 18 '15 at 13:51
Bad idea, you'll forever regret this when you need to localize your app. Simply use a lookup table. — Hans Passant, Jan 18 '15 at 13:54
possible duplicate of [Get DescriptionAttribute from enum](http://stackoverflow.com/questions/15233780/get-descriptionattribute-from-enum) — John Alexiou, Jan 18 '15 at 16:05
It is recommended to use the `[DescriptionAttribute()]`. This is exactly why it exists so you don't have to re-invent the wheel. — John Alexiou, Jan 18 '15 at 16:06

score 3 · Answer 1 · edited Nov 04 '20 at 14:59

3

You can write own extension method:

public static string ToFormattedText(this MyEnum value)
{
    var stringVal = value.ToString();   
    var bld = new StringBuilder();

    for (var i = 0; i < stringVal.Length; i++)
    {
        if (char.IsUpper(stringVal[i]))
        {
            bld.Append(" ");
        }

        bld.Append(stringVal[i]);
    }

    return bld.ToString();
}

If you want method available for all enums, just replace MyEnum with Enum.

Usage:

var test = MyEnum.SampleName.ToFormattedText();

Consider caching - building string everytime could not be efficient.

edited Nov 04 '20 at 14:59

Steve Johnson

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answered Jan 18 '15 at 13:44

I see. Thanks. I wanted more built-in way. – YAKOVM Jan 18 '15 at 13:48
there is no built-in way. you can't override enum's ToString. – Selman Genç Jan 18 '15 at 13:50
There is no built-in ways to add spaces in such way. Why proposed solution cannot be used? – Jan 18 '15 at 13:51
@pwas You could use `for (var i = 1;...` and eliminate the test for `i > 0`. – Andrew Morton Jan 18 '15 at 14:05

score 2 · Answer 2 · answered Jan 18 '15 at 16:09

Use the Description attribute to decortate your enumeration values. I'd suggest adding a resx file for resources so that you can localise more easily. If you hardcoded "Memory Failure", it becomes more work to be able to change that to another language (as Hans Passant mentioned in the comments).

public enum FailureDescription
{
    [Description("Memory Failure")] //hardcoding English
    MemoryFailure,
    [Description(MyStringsResourceFile.FragmentationDescription)] //reading from a resx file makes localisation easier
    Fragmentation,
    [Description(MyStringsResourceFile.SegmentationFaultDescription)]
    SegmentationFault
}

You can then create a method, or extension method (as shown) to read the Description value.

public static class Extensions
{
    public static string GetDescription(this Enum value)
    {

        FieldInfo fi = value.GetType().GetField(value.ToString());

        DescriptionAttribute[] attributes =
            (DescriptionAttribute[])fi.GetCustomAttributes(
            typeof(DescriptionAttribute),
            false);

        if (attributes != null &&
            attributes.Length > 0)
            return attributes[0].Description;
        else
            return value.ToString();
    }
}

Then call the method like so

Console.WriteLine(FailureDescription.MemoryFailure.GetDescription());

...if only the `resx` files weren't so damm hard to maintain ;-] — t3chb0t, Jan 18 '15 at 16:18

score 1 · Answer 3 · answered Jan 19 '15 at 04:51

This extension method will do it for you:

public static string ToFormattedText(this FailureDescription value)
{
    return new string(value.ToString()
        .SelectMany(c =>
            char.IsUpper(c)
            ? new [] { ' ', c }
            : new [] { c })
        .ToArray()).Trim();
}

score 0 · Answer 4 · answered Jan 18 '15 at 15:52

You also can use a simple regex & linq mixture to extract and concatenate the words:

var withSpaces = 
    Regex
    .Matches(
        FailureDescription.MemoryFailureTest.ToString(), 
        @"([A-Z][a-z]+)(?=[A-Z]|$)")
    .Cast<Match>()
    .Select(m => m.Groups[1].Value)
    .Aggregate((str, next) => (str = str + " " + next));

DEMO at ideone.com

where:

([A-Z][a-z]+)(?=[A-Z]|$)

matches words that begin with upper-case letters until the next upper-case letter or the end of string is found: DEMO at regex101

.Select(m => m.Groups[1].Value)

selects the matched values from the group 1

.Aggregate((str, next) => (str = str + " " + next));

concatenates words and inserts a space between them.

score 0 · Answer 5 · answered Jan 19 '15 at 04:39

Here is one of the utilities I've been using. @HansPassant in his comment raised a good point about localizing.

This code takes Resource files into consideration. In the attribute with two params first param is the Key in Resource file, where as the second param is the namespace for the resource.

Checkout the git repo https://github.com/seanpaul/EnumExtensions

public enum TestEnum
{
    //You can pass what ever string value you want
    [StringValue("From Attribute")]
    FromAttribute = 1,

    //If localizing, you can use resource files
    //First param is Key in resource file, second is namespace for Resources.
    [StringValue("Test", "EnumExtensions.Tests.Resources")]
    FromResource = 2,

    //or don't mention anything and it will use built-in ToString
    BuiltInToString = 3
}

[Test ()]
public void GetValueFromAttribute ()
{
    var testEnum = TestEnum.FromAttribute;
    Assert.AreEqual ("From Attribute", testEnum.GetStringValue ());
}
[Test ()]
public void GetValueFromResourceFile ()
{
    var testEnum = TestEnum.FromResource;
    Assert.AreEqual ("From Resource File", testEnum.GetStringValue ());
}

score 0 · Answer 6 · answered Jun 05 '20 at 22:16

An elegant solution following the DRY and KISS principles would be using Humanizer:

"Memory Failure".DehumanizeTo<EnumUnderTest>(); // Returns FailureDescription.MemoryFailure.
"Fragmentation".DehumanizeTo<EnumUnderTest>(); // Returns FailureDescription.Fragmentation.
"Segmentation Fault".DehumanizeTo<EnumUnderTest>(); // Returns FailureDescription.SegmentationFault.

Convert enum to string having a space

6 Answers6