StrEnum 2.0.4

StrEnum

StrEnum is a tiny library for creating string-based enums in C#. Use strings instead of integers for richer, more meaningful data while keeping type safety. Read more about when and why to use string enums in this blog post.

StrEnum targets .NET Standard 2.0 and has no external dependencies.

Ecosystem

These companion packages plug StrEnum into the rest of the .NET ecosystem:

• StrEnum.AspNetCore — bind string enums in ASP.NET Core controllers.
• StrEnum.EntityFrameworkCore — use string enums in EF Core queries and migrations.
• StrEnum.Npgsql — map string enums to native Postgres enum types via Npgsql and EF Core.
• StrEnum.Dapper — use string enums in Dapper commands and queries.
• StrEnum.System.Text.Json — JSON serialization and deserialization with System.Text.Json.

Installation

Install StrEnum via the .NET CLI:

dotnet add package StrEnum

Usage

Defining a string enum

Inherit from StringEnum<TEnum> and use Define to declare members:

public class Sport : StringEnum<Sport>
{
    public static readonly Sport TrailRunning = Define("TRAIL_RUNNING");
    public static readonly Sport RoadCycling = Define("ROAD_CYCLING");
}

The field name becomes the member's name; the argument to Define becomes its value.

Working with members

Members behave like a regular enum — including ToString, casting, and equality:

var sport = Sport.TrailRunning;

sport.ToString();           // "TrailRunning"
(string)sport;              // "TRAIL_RUNNING"
sport == Sport.RoadCycling; // false

Parsing

Parse converts a name or value into the matching member, throwing if no match is found:

Sport.Parse("TrailRunning");  // Sport.TrailRunning
Sport.Parse("TRAIL_RUNNING"); // Sport.TrailRunning
Sport.Parse("Quidditch");     // throws ArgumentException: "Requested name or value 'Quidditch' was not found."

Pass ignoreCase: true for case-insensitive matching:

Sport.Parse("trailrunning",  ignoreCase: true); // Sport.TrailRunning
Sport.Parse("trail_running", ignoreCase: true); // Sport.TrailRunning

Pass MatchBy.ValueOnly to match by value and skip member names:

Sport.Parse("TRAIL_RUNNING", matchBy: MatchBy.ValueOnly); // Sport.TrailRunning
Sport.Parse("TrailRunning",  matchBy: MatchBy.ValueOnly); // throws ArgumentException

Use TryParse for the non-throwing variant:

Sport.TryParse("TrailRunning", out var trailRunning); // true,  trailRunning == Sport.TrailRunning
Sport.TryParse("Quidditch",    out var quidditch);    // false, quidditch == null

Listing members

GetMembers returns members in declaration order:

Sport.GetMembers(); // [Sport.TrailRunning, Sport.RoadCycling]

Switch statements and expressions

Because string enum members aren't constants, use property patterns with when guards:

switch (sport)
{
    case { } when sport == Sport.TrailRunning:
        PutOnTrailShoes();
        break;
    case { } when sport == Sport.RoadCycling:
        GetOnRoadBike();
        break;
}

The same pattern works in switch expressions:

var sportName = sport switch
{
    _ when sport == Sport.TrailRunning => "Trail Running",
    _ when sport == Sport.RoadCycling  => "Road Cycling",
    _                                  => "Not yet known"
};

Adding members at runtime

Define is protected, but you can expose it through a public method to add members after the class is initialized:

public class FictionalSport : StringEnum<FictionalSport>
{
    public static readonly FictionalSport Quidditch = Define("QUIDDITCH");

    public static FictionalSport Add(string name, string value) => Define(value, name);
}

Both name and value must be supplied for members added this way:

var podracing = FictionalSport.Add("Podracing", "PODRACING");

(string)podracing;                            // "PODRACING"
FictionalSport.Parse("Podracing").ToString(); // "Podracing"

License

Copyright © 2026 Dmytro Khmara.

StrEnum is licensed under the MIT license.