Created
March 22, 2019 17:09
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C# generic enumeration
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public sealed class ExampleEnumeration : Enumeration<ExampleEnumeration, string> | |
{ | |
public static readonly ExampleEnumeration Value = new ExampleEnumeration(nameof(Value)); | |
public static readonly ExampleEnumeration Value2 = new ExampleEnumeration(nameof(Value2), "Value 2"); | |
private ExampleEnumeration(string value, string name = null) : base(value, name ?? value) {} | |
} | |
/// <summary> | |
/// Enumeration representation that can take all types | |
/// </summary> | |
/// <typeparam name="TEnum">The derived type that inherits from this base class (CRTP)</typeparam> | |
/// <typeparam name="TValue">The type of the value of the enum</typeparam> | |
public abstract class Enumeration<TEnum, TValue> : IComparable | |
where TEnum : Enumeration<TEnum, TValue> | |
where TValue: class, IComparable | |
{ | |
private static readonly Dictionary<string, Enumeration<TEnum, TValue>> Mapping = new Dictionary<string, Enumeration<TEnum, TValue>>(); | |
public TValue Value { get; } | |
public string Name { get; } | |
static Enumeration() | |
{ | |
// Ensure that we set up the derived class's enum members to fill the "Mapping" dictionary | |
System.Runtime.CompilerServices.RuntimeHelpers.RunClassConstructor(typeof(TEnum).TypeHandle); | |
} | |
protected Enumeration(TValue enumValue, string name) | |
{ | |
Value = enumValue; | |
Name = name; | |
Mapping.Add(name, this); | |
} | |
public static TEnum Parse(string name) | |
{ | |
if (Mapping.TryGetValue(name, out var result)) | |
{ | |
return (TEnum)result; | |
} | |
throw new InvalidCastException(); | |
} | |
public static IEnumerable<TEnum> All => Mapping.Values.AsEnumerable().Cast<TEnum>(); | |
public override string ToString() { return Name; } | |
public override bool Equals(object obj) | |
{ | |
if (!(obj is TEnum otherValue)) | |
return false; | |
return Value.Equals(otherValue.Value); | |
} | |
public int CompareTo(object other) => Value.CompareTo(((TEnum)other).Value); | |
public override int GetHashCode() | |
{ | |
return 2108858624 + Value.GetHashCode(); | |
} | |
} |
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