C#•2y ago

interface instead of mapping one by one

hi all, im trying to use an interface to initialize common properties, for example INote that contains all common properties, and multiple classes will inherit from this INote, im trying to achieve something like : initialize once and can be used for all objects that inherit this INote interface previously i was doing one by one mapping for each objects that have common properties and found out there are lots of duplication (some resource say better to do manual mapping that use a library like automapper) so i try to do it using interface, but somehow even if a class inherit this INote i still can't do it like this : Memo resource = QueryVariant(new NoteItem(), "memo"); LongNote longNote = QueryVariant(new NoteItem(), "longNote"); did i miss anything here?

public interface INote{
  public long NodeId { get; set; }
  public string NoteName { get; set; }
}

public class LongNote : INote {
  
  public long NodeId { get; set; }
  public string NoteName { get; set; }

  public string barcodeID {get;set;}
  public string profileURL {get;set;}
}
 
public class Memo: INote {
  
  public long NodeId { get; set; }
  public string NoteName { get; set; }

  public string memoURL {get;set;}
  public string memoUniqueID {get;set;}
}

Memo resource = QueryVariant(new NoteItem(), "memo"); //doesnt work

private async Task<INote> QueryVariant(NoteItem item, string type) {
  INote note = type switch {
    "memo" => new Memo { /*initialize properties here*/ };
    // replicate for the other types
    _ => // throw some exception here
  };
  // initialize common properties in note here, i.e:
  note.id = item.Id.ToString():
  note.noteName = item.name;
  // etc
  return note;
}

public interface INote{
  public long NodeId { get; set; }
  public string NoteName { get; set; }
}

public class LongNote : INote {
  
  public long NodeId { get; set; }
  public string NoteName { get; set; }

  public string barcodeID {get;set;}
  public string profileURL {get;set;}
}
 
public class Memo: INote {
  
  public long NodeId { get; set; }
  public string NoteName { get; set; }

  public string memoURL {get;set;}
  public string memoUniqueID {get;set;}
}

Memo resource = QueryVariant(new NoteItem(), "memo"); //doesnt work

private async Task<INote> QueryVariant(NoteItem item, string type) {
  INote note = type switch {
    "memo" => new Memo { /*initialize properties here*/ };
    // replicate for the other types
    _ => // throw some exception here
  };
  // initialize common properties in note here, i.e:
  note.id = item.Id.ToString():
  note.noteName = item.name;
  // etc
  return note;
}

6 Replies

Becquerel•2y ago

I'm not sure why you're using an interface for this instead of inheritance

(some resource say better to do manual mapping that use a library like automapper)

doesn't necessarily mean they're right!

Memo resource = QueryVariant(new NoteItem(), "memo"); //doesnt work

this doesn't work because your QueryVariant method only takes one parameter. it doesn't take a string parameter that you're trying to pass in

joy•2y ago

I see.. so it's okay if i use automapper, is that right? (Actually I'm not sure of a best practice for this problem, hope you could give an advice as well ..) I was trying to map an object one by one previously (object with common properties, so there are redudancy everywhere..) Sry i mistyped the code, it should accept 2 parameters (edited the message), but i mean.. I can't seem to convert it that way

Becquerel•2y ago

Automapper is a useful tool for this kind of situation when people warn against automapper it's usually because people try to use it for important business logic Memo resource = QueryVariant(new NoteItem(), "memo"); //doesnt work QueryVariant returns an INote all Memos are INotes, but not all INotes are Memos you are trying to assign an INote (less specific) to a Memo (more specific) assigning a Memo (more specific) to an INote (less specific) would work

joy•2y ago

I see.. okay understand.. I'll revert my changes to use inheritance instead of interface and use automapper for the current problem I see, no wonder it wont works.., i think there would be lot's of work on using interface for this issue Okay.. thank you for your explanation, noted it down.. 🙏

Becquerel•2y ago

no prob 🙂

joy•2y ago

🍀

Gaming

Programming

interface instead of mapping one by one