How do I map enums in many-to-one relationship-CodePudding

I have two enums, the source one is with responses from api and another one is what I want to send to frontend.

public enum ApiResponse
{
    A=1,
    B=2,
    C=3,
    D=4
}


public enum DestEnum
{
    A=1,
    BCD=2
}

What I am trying to do is:

public class ExampleViewModel
{
    public DestEnum foo { get; set; }
}

var response = ApiResponse.C;

result = new ExampleViewModel()
{
    foo = response
};

And I want foo value to be DestEnum.BCD Is it possible to do with automapper or some custom attributes?

CodePudding user response：

Assuming you've set your serializer up to send strings already you seem to be just looking for a way to map an X to a Y

How about:

public static class EnumExtensions{
  static Dictionary<ApiResponse,DestEnum> _mapDest = 
  new() {
      [ApiResponse.A] = DestEnum.A,
      [ApiResponse.B] = DestEnum.BCD,
      [ApiResponse.C] = DestEnum.BCD,
      [ApiResponse.D] = DestEnum.BCD,
      
  };
    
  public static DestEnum AsDest(this ApiResponse x) => _mapDest[x];
}

And then you can convert the ApiRespnse you got to a Dest like:

return new BlahViewModel{

  DestEnumProperty = apiResponseEnumValueIGot.AsDest(),
  OtherProp = ...
}

Warning, the lookup will blow up if you get any values that aren't mapped; if you think this will ever be possible, consider having an Unknown value in your DestEnum and doing something like:

=> _mapDest.TryGetValue(x, out var r) ? r : DestEnum.Unknown