using System;

​

public abstract record SaveNoteMessage(string CustomerName);

​

public record SavePartyNoteMessage(string CustomerName, int PartyNo) : SaveNoteMessage(CustomerName);

​

public record SaveContractNoteMessage(string CustomerName, int ContractId) : SaveNoteMessage(CustomerName);

​

public class Program

{

    public void SaveNote(SavePartyNoteMessage msg) {

        Console.WriteLine("Saving party note with Party NO: " + msg.PartyNo);

    }

    public void SaveNote(SaveContractNoteMessage msg) {

        Console.WriteLine("Saving contract note with Contract ID: " + msg.ContractId);

    }

    public static void Main()

    {

        //var noteMessage = new SavePartyNoteMessage("Craig", 23);

        var noteMessage = new SaveContractNoteMessage("Craig", 200);

        new Program().SaveNote(noteMessage);

    }

}