Initial idea for benchmarking is from Nick Chapsas video: https://youtu.be/BoE5Y6Xkm6w
The Enumeration base class is based on this article: https://docs.microsoft.com/en-us/dotnet/architecture/microservices/microservice-ddd-cqrs-patterns/enumeration-classes-over-enum-types
.
└── Demo.EnumVsEnumeration.BenchmarkTests
- Benchmark - https://github.com/dotnet/BenchmarkDotNet
| Method | Mean | Error | StdDev | Median | Gen 0 | Allocated |
|--------------------------------- |--------------:|-----------:|-----------:|--------------:|-------:|----------:|
| NativeEnumValueToString | 32.1648 ns | 0.6373 ns | 0.5649 ns | 32.0189 ns | 0.0038 | 24 B |
| NativeEnumAllValuesToString | 1,236.8316 ns | 23.4125 ns | 36.4505 ns | 1,232.6040 ns | 0.0782 | 496 B |
| EnumerationValueToString | 0.0081 ns | 0.0210 ns | 0.0288 ns | 0.0000 ns | - | - |
| EnumerationListAllValuesToString | 131.7649 ns | 2.6642 ns | 5.8479 ns | 130.0606 ns | 0.0433 | 272 B |
| EnumerationGetAllValuesToString | 524.3484 ns | 10.4138 ns | 14.9352 ns | 518.5165 ns | 0.0544 | 344 B |
Its worthwhile to notice that a type based on Enumeration can contain pre-assigned display name, and therefore the conversion does not allocate any memory when accessing this name.
The native Enum has to execute binary search in order to find out the correct enum value which can be O (log n).
public override string ToString()
{
// Returns the value in a human readable format. For PASCAL style enums who's value maps directly the name of the field is returned.
// For PASCAL style enums who's values do not map directly the decimal value of the field is returned.
// For BitFlags (indicated by the Flags custom attribute): If for each bit that is set in the value there is a corresponding constant
// (a pure power of 2), then the OR string (ie "Red, Yellow") is returned. Otherwise, if the value is zero or if you can't create a string that consists of
// pure powers of 2 OR-ed together, you return a hex value
// Try to see if its one of the enum values, then we return a String back else the value
return InternalFormat((RuntimeType)GetType(), ToUInt64()) ?? ValueToString();
}
private static string? InternalFormat(RuntimeType enumType, ulong value)
{
EnumInfo enumInfo = GetEnumInfo(enumType);
if (!enumInfo.HasFlagsAttribute)
{
return GetEnumName(enumInfo, value);
}
else // These are flags OR'ed together (We treat everything as unsigned types)
{
return InternalFlagsFormat(enumType, enumInfo, value);
}
}
private static string? GetEnumName(EnumInfo enumInfo, ulong ulValue)
{
int index = Array.BinarySearch(enumInfo.Values, ulValue);
if (index >= 0)
{
return enumInfo.Names[index];
}
return null; // return null so the caller knows to .ToString() the input
}