using System;

using System.Text.Json;

using System.Text.Json.Serialization;

​

public class Program

{

    public static void Main()

    {

        static void TryDeserialize<T>(string json, string label)

        {

            try 

            {

                var contact = JsonSerializer.Deserialize<T>(json);

                Console.WriteLine($"{label}: OK, type = {contact}");

            }

            catch (Exception e)

            {

                Console.WriteLine($"{label}: FAIL, message = {e.Message}");

            }

        }

        var jsonNum = "{ \"type\": 1 }";

        var jsonStr = "{ \"type\": \"Phone\" }";

        TryDeserialize<Contact1>(jsonNum, "Contact1 (JsonPropertyName)");

        TryDeserialize<Contact1>(jsonStr, "Contact1 (JsonPropertyName)");

​

        TryDeserialize<Contact2>(jsonNum, "Contact2 (EnumMember)");

        TryDeserialize<Contact2>(jsonStr, "Contact2 (EnumMember)");

​

        TryDeserialize<Contact3>(jsonNum, "Contact3 (JsonStringEnumConverter)");

        TryDeserialize<Contact3>(jsonStr, "Contact3 (JsonStringEnumConverter)");

    }

    public class Contact1

    {

        [JsonPropertyName("type")]

        public ContactType1? Type { get; set; } 

        public override string ToString() => Type?.ToString() ?? "null";

    }

    public enum ContactType1

    {

        [JsonPropertyName(@"Email")]

        Email,

        [JsonPropertyName(@"Phone")]

        Phone

    }

    public class Contact2

    {

        [JsonPropertyName("type")]

        public ContactType2? Type { get; set; } 

        public override string ToString() => Type?.ToString() ?? "null";

    }

    public enum ContactType2

    {

        [System.Runtime.Serialization.EnumMember(Value = @"Email")]

        Email,

​

        [System.Runtime.Serialization.EnumMember(Value = @"Phone")]

        Phone

    }

    public class Contact3

    {

        [JsonPropertyName("type")]

        [JsonConverter(typeof(JsonStringEnumConverter))]

        public ContactType3? Type { get; set; } 

        public override string ToString() => Type?.ToString() ?? "null";

    }

    public enum ContactType3

    {

        Email,

        Phone

    }

}