using System.Collections;
using System.Collections.Generic;
using System.Runtime.Serialization.Formatters;
using System.ComponentModel.DataAnnotations;
using System.Globalization;
using System.Collections.ObjectModel;
using System.Text.Json.Serialization;
using System.Text.Json.Serialization.Metadata;
using System.Text.Json.Nodes;
public class NamingPolicyJsonElementConverter : JsonConverter<JsonElement>
public override void Write(Utf8JsonWriter writer, JsonElement value, JsonSerializerOptions options)
var namingPolicy = options.PropertyNamingPolicy;
case JsonValueKind.Object:
writer.WriteStartObject();
foreach (var pair in value.EnumerateObject())
writer.WritePropertyName(namingPolicy?.ConvertName(pair.Name) ?? pair.Name);
Write(writer, pair.Value, options);
case JsonValueKind.Array:
writer.WriteStartArray();
foreach (var item in value.EnumerateArray())
Write(writer, item, options);
public override JsonElement Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) => JsonSerializer.Deserialize<JsonElement>(ref reader);
public string Name { get; set; }
public object Data { get; set; }
public static void Test()
var inputJson = GetJson();
var inOptions = new JsonSerializerOptions
PropertyNamingPolicy = null,
AllowTrailingCommas = true,
var outOptions = new JsonSerializerOptions
Converters = { new NamingPolicyJsonElementConverter() },
PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
var model = JsonSerializer.Deserialize<Model>(inputJson, inOptions);
var outputJson = JsonSerializer.Serialize(model, outOptions);
Console.WriteLine("Re-serialized JSON:");
Console.WriteLine(outputJson);
Assert.That(outputJson.Contains("\"data\":"));
Assert.That(outputJson.Contains("\"glossDef\":"));
Assert.That(outputJson.Contains("\"glossSeeAlso\":"));
Console.WriteLine("\nOriginal JSON:");
Console.WriteLine(inputJson);
static string GetJson() =>
""Title"":""example glossary"",
""GlossTerm"":""Standard Generalized Markup Language"",
""Abbrev"":""ISO 8879:1986"",
""PARA"":""A meta-markup language, used to create markup languages such as DocBook."",
public static void Main()
Console.WriteLine("Environment version: {0} ({1}), {2}", System.Runtime.InteropServices.RuntimeInformation.FrameworkDescription , Environment.Version, Environment.OSVersion);
Console.WriteLine("System.Text.Json version: " + typeof(JsonSerializer).Assembly.FullName);
Console.WriteLine("Failed with unhandled exception: ");