using System;

using System.Text.Json;

​

public class Program

{

    public static void Main()

    {

        Invoice fullInvoice = new Invoice

        {

            Id = "id-12345",

            Vendor = new Vendor { Id = "vendorId", Name = "vendor name", BankAccount = "123asd123asd" },

            Total = 100.00m,

            Status = "st-Paid",

            DeliveryCount = 1,

            HeldToDate = DateTime.Now.AddDays(30),

            ErrorCode = "err-0",

            DownloadedDate = DateTime.Now,

            ImportMsg = "some import message",

        };

​

        var makeJsonPrettyOption = new JsonSerializerOptions { WriteIndented = true };

        var fullInvoiceJson = JsonSerializer.Serialize(fullInvoice, makeJsonPrettyOption);

        var reducedInvoiceJson = JsonSerializer.Serialize<IReducedInvoice>(fullInvoice, makeJsonPrettyOption);

​

        Console.WriteLine($"fullInvoice\n{fullInvoiceJson}");

        Console.WriteLine($"reducedInvoice\n{reducedInvoiceJson}");

    }

​

    public class Invoice : IReducedInvoice

    {

        public string Id { get; set; }

        public Vendor Vendor { get; set; }

        public decimal Total { get; set; }

        public string Status { get; set; }

        public int DeliveryCount { get; set; }

        public object HeldToDate { get; set; }

        public string ErrorCode { get; set; }

        public DateTime DownloadedDate { get; set; }

        public string ImportMsg { get; set; }

        IReducedVendor IReducedInvoice.Vendor { get => Vendor; }

    }

    public class Vendor : IReducedVendor

    {

        public string Id { get; set; }

        public string Name { get; set; }

        public string BankAccount { get; set; }

    }

​

    public interface IReducedInvoice

    {

        public string Id { get; set; }

        public IReducedVendor Vendor { get; }

        public decimal Total { get; set; }

        public string Status { get; set; }

    }

    public interface IReducedVendor

    {

        public string Id { get; set; }

        public string Name { get; set; }        

    }

}