C#•7mo ago

String enums - current consensus

Hi! What is the current consensus on string enum Any special library, Some abstract class that defines helper methods with attributes etc. Example usage:

public enum AuthTokenStatus {
    ACTIVE = 'Y',
    INACTIVE = 'N'
}

public enum AuthTokenStatus {
    ACTIVE = 'Y',
    INACTIVE = 'N'
}

13 Replies

The Fog from Human Resources•7mo ago

afaik enums are numbers

IndeedOP•7mo ago

I understand that My point is how does one go about implementing custom string enums in c# What is the currently agreed upon standard

The Fog from Human Resources•7mo ago

technically you could do

public enum AuthTokenStatus {
    ACTIVE = 1,
    INACTIVE = 0
}

public enum AuthTokenStatus {
    ACTIVE = 1,
    INACTIVE = 0
}

IndeedOP•7mo ago

some Enumeration abstract class like so

public abstract class Enumeration : IComparable
{
    public string Name { get; private set; }

    public int Id { get; private set; }

    protected Enumeration(int id, string name) => (Id, Name) = (id, name);

    public override string ToString() => Name;

    public static IEnumerable<T> GetAll<T>() where T : Enumeration =>
        typeof(T).GetFields(BindingFlags.Public |
                            BindingFlags.Static |
                            BindingFlags.DeclaredOnly)
                 .Select(f => f.GetValue(null))
                 .Cast<T>();

    public override bool Equals(object obj)
    {
        if (obj is not Enumeration otherValue)
        {
            return false;
        }

        var typeMatches = GetType().Equals(obj.GetType());
        var valueMatches = Id.Equals(otherValue.Id);

        return typeMatches && valueMatches;
    }

    public int CompareTo(object other) => Id.CompareTo(((Enumeration)other).Id);

    // Other utility methods ...
}

public abstract class Enumeration : IComparable
{
    public string Name { get; private set; }

    public int Id { get; private set; }

    protected Enumeration(int id, string name) => (Id, Name) = (id, name);

    public override string ToString() => Name;

    public static IEnumerable<T> GetAll<T>() where T : Enumeration =>
        typeof(T).GetFields(BindingFlags.Public |
                            BindingFlags.Static |
                            BindingFlags.DeclaredOnly)
                 .Select(f => f.GetValue(null))
                 .Cast<T>();

    public override bool Equals(object obj)
    {
        if (obj is not Enumeration otherValue)
        {
            return false;
        }

        var typeMatches = GetType().Equals(obj.GetType());
        var valueMatches = Id.Equals(otherValue.Id);

        return typeMatches && valueMatches;
    }

    public int CompareTo(object other) => Id.CompareTo(((Enumeration)other).Id);

    // Other utility methods ...
}

public class CardType
    : Enumeration
{
    public static CardType Amex = new(1, nameof(Amex));
    public static CardType Visa = new(2, nameof(Visa));
    public static CardType MasterCard = new(3, nameof(MasterCard));

    public CardType(int id, string name)
        : base(id, name)
    {
    }
}

public class CardType
    : Enumeration
{
    public static CardType Amex = new(1, nameof(Amex));
    public static CardType Visa = new(2, nameof(Visa));
    public static CardType MasterCard = new(3, nameof(MasterCard));

    public CardType(int id, string name)
        : base(id, name)
    {
    }
}

some library handling it in compiletime etc. there are many ways to go on about it, which is currently proposed to be the best one

The Fog from Human Resources•7mo ago

Arent Enumerations things you loop over?

IndeedOP•7mo ago

you're talking about Enumerables most go for static readonly strings the point is I later deserialize them in dapper into values to use in queries

    public async Task<Result<IEnumerable<AuthTokenDTO>>> GetTokensByUser(int idUser, AuthTokenStatus[]? statuses = null, AuthProvider[]? providers = null) {
        statuses ??= [AuthTokenStatus.ACTIVE];
        
        
        Result<IEnumerable<AuthTokenDTO>> tokens =  await Result.Try(() => {
                string query = """
                    SELECT id, idUser, provider, authToken, createdAt, updatedAt, status 
                    FROM crud.auth 
                    WHERE idUser = @idUser
                    AND status IN (@statuses)
                """;
                
                if (providers is { Length: > 0 }) {
                    query += " AND provider IN (@providers)";
                }

                return this._context.GetConnection().QueryAsync<AuthTokenDTO>(query, new {
                    providers,
                    statuses,
                    idUser
                });
            });

        if (tokens.IsFailed) {
            return Result.Fail("Failed to fetch auth tokens").WithErrors(tokens.Errors);
        }

        return tokens;
    }

    public async Task<Result<IEnumerable<AuthTokenDTO>>> GetTokensByUser(int idUser, AuthTokenStatus[]? statuses = null, AuthProvider[]? providers = null) {
        statuses ??= [AuthTokenStatus.ACTIVE];
        
        
        Result<IEnumerable<AuthTokenDTO>> tokens =  await Result.Try(() => {
                string query = """
                    SELECT id, idUser, provider, authToken, createdAt, updatedAt, status 
                    FROM crud.auth 
                    WHERE idUser = @idUser
                    AND status IN (@statuses)
                """;
                
                if (providers is { Length: > 0 }) {
                    query += " AND provider IN (@providers)";
                }

                return this._context.GetConnection().QueryAsync<AuthTokenDTO>(query, new {
                    providers,
                    statuses,
                    idUser
                });
            });

        if (tokens.IsFailed) {
            return Result.Fail("Failed to fetch auth tokens").WithErrors(tokens.Errors);
        }

        return tokens;
    }

The Fog from Human Resources•7mo ago

why not use that fancy EF Core stuff i heard its bad practice to write raw SQL queries but i have no idea abt that stuff yet so :stare:

IndeedOP•7mo ago

Different people, different needs Some people need fine-grained queries for their needs It can be better for optimization and suiting one's specific needs without fighting with EFCore

Core•7mo ago

If you need something similar to enum just with strings then you could do the following:

c#
public static class SortOrder
{
    public const string Ascending = "asc";

    public const string Descending = "desc";
}

c#
public static class SortOrder
{
    public const string Ascending = "asc";

    public const string Descending = "desc";
}

IndeedOP•7mo ago

I apologize however I do not believe we understand each other, as I have already mentioned this solution and have also explained my usage and why it might not necessarily work with my current setup I'll try Intellenum for now, but I am open to suggestions for reference:

[Intellenum(typeof(string))]
public partial class CustomerType {
    public static readonly CustomerType Basic = new ("Basic");
}

[Intellenum(typeof(string))]
public partial class CustomerType {
    public static readonly CustomerType Basic = new ("Basic");
}

Angius•7mo ago

https://github.com/andrewlock/NetEscapades.EnumGenerators

[EnumExtensions]
public enum AuthTokenStatus 
{
    [Display(Name = "Y")]
    Active,
    [Display(Name = "N")]
    Inactive,
}

[EnumExtensions]
public enum AuthTokenStatus 
{
    [Display(Name = "Y")]
    Active,
    [Display(Name = "N")]
    Inactive,
}

and use .ToStringFast() instead of .ToString()

IndeedOP•7mo ago

Thank you! Looks nice Quick question though, Do you happen to know if there is a way to add a dapper anonymous parameter converter to it so I do not have to map these enums into values before sending them in a query?

IndeedOP•7mo ago

Nevermind! Found it! https://andydote.co.uk/2014/07/22/configuring-dapper-to-work-with-custom-types/ I can do reflectionbased setup during initialization of the server https://andydote.co.uk/2014/07/22/configuring-dapper-to-work-with-custom-types/

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String enums - current consensus