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 NamingPolicyJsonNodeConverter : JsonConverter<JsonNode>
public override bool CanConvert(Type typeToConvert) => typeof(JsonNode).IsAssignableFrom(typeToConvert) && !typeof(JsonValue).IsAssignableFrom(typeToConvert);
public override void Write(Utf8JsonWriter writer, JsonNode? value, JsonSerializerOptions options)
var namingPolicy = options.PropertyNamingPolicy;
writer.WriteStartObject();
foreach (var pair in obj)
writer.WritePropertyName(namingPolicy?.ConvertName(pair.Key) ?? pair.Key);
Write(writer, pair.Value, options);
writer.WriteStartArray();
foreach (var item in array)
Write(writer, item, options);
value.WriteTo(writer, options);
public override JsonNode? Read(ref Utf8JsonReader reader, Type typeToConvert, JsonSerializerOptions options) => JsonNode.Parse(ref reader);
public static void Test()
var inputJson = GetJson();
var options = new JsonSerializerOptions
Converters = { new NamingPolicyJsonNodeConverter() },
PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
var node = JsonNode.Parse(inputJson);
var outputJson = JsonSerializer.Serialize(node, options);
Console.WriteLine("Re-serialized JSON:");
Console.WriteLine(outputJson);
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: ");