using System;

using System.Collections.Generic;

using System.Linq;

using System.Text.Json;

using System.Text.Json.Serialization;

​

public class Program

{

        const string inJson = @"[{

            ""id"": 123,

            ""firstName"": ""James"",

            ""lastName"": ""Smith"",

            ""group"": ""Premium"",

            ""state"": ""Active""

        }]";

​

    public static void Main()

    {

        var deserialized = JsonSerializer.Deserialize<List<JsonMember>>(inJson);

        var asMembership = deserialized.Select(i => new Membership(i)).ToList();

        foreach(var m in asMembership){

            Console.WriteLine($"Group: {m.Group}");

            Console.WriteLine($"Group: {m.State}");

            Console.WriteLine($"Member Id: {m.Member.Id}");

            Console.WriteLine($"Member First Name: {m.Member.FirstName}");

            Console.WriteLine($"Member Last Name: {m.Member.LastName}");

        }

    }

}

​

public class JsonMember{

    [JsonPropertyName("id")]

    public int Id { get; set; }

​

    [JsonPropertyName("firstName")]

    public string FirstName { get; set; }

​

    [JsonPropertyName("lastName")]

    public string LastName { get; set; }

​

    [JsonPropertyName("group")]

    public string Group { get; set; }

​

    [JsonPropertyName("state")]

    public string State { get; set; }

}

​

public class Membership

{

    public Member Member { get; set; }

    public string Group { get; set; }

    public string State { get; set; }

    public Membership(JsonMember jsonMember){

        Group = jsonMember.Group;

        State = jsonMember.State;

        Member = new Member{

            Id = jsonMember.Id,

            FirstName = jsonMember.FirstName,

            LastName = jsonMember.LastName

        };

    }

}

​

public class Member

{

    public int Id { get; set; }

    public string FirstName { get; set; }

    public string LastName { get; set; }

}