using System;

using System.Collections;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Runtime.Serialization.Formatters;

using System.IO;

using System.Data;

using System.ComponentModel.DataAnnotations;

using System.Globalization;

using System.Reflection;

​

using Newtonsoft.Json;

using Newtonsoft.Json.Linq;

using Newtonsoft.Json.Converters;

using Newtonsoft.Json.Serialization;    

​

using NUnit.Framework; // Throws NUnit.Framework.AssertionException

​

//https://stackoverflow.com/questions/54353428/how-to-unescape-unicode-in-json-net

​

    public static partial class JsonExtensions

    {

        // Adapted from this answer https://stackoverflow.com/a/30329731

        // To https://stackoverflow.com/q/2661063

        // By Duncan Smart https://stackoverflow.com/users/1278/duncan-smart

        public static string JsonPrettify(string json, Formatting formatting = Formatting.Indented)

        {

            using (var stringReader = new StringReader(json))

            using (var stringWriter = new StringWriter())

            {

                return JsonPrettify(stringReader, stringWriter, formatting).ToString();

            }

        }

        public static TextWriter JsonPrettify(TextReader textReader, TextWriter textWriter, Formatting formatting = Formatting.Indented)

        {

            // Let caller who allocated the the incoming readers and writers dispose them also

            // Disable date recognition since we're just reformatting

            using (var jsonReader = new JsonTextReader(textReader) { DateParseHandling = DateParseHandling.None, CloseInput = false })

            using (var jsonWriter = new JsonTextWriter(textWriter) { Formatting = formatting, CloseOutput = false })

            {

                jsonWriter.WriteToken(jsonReader);

            }

            return textWriter;

        }

    }

​

    class TestClass

    {

        public static void Test()

        {

            var json = @"{ ""val1"": ""\u003c=AA+ \u003e=AA-"", ""val2"": ""\\\/\""\b\n\r\t\u003c""}";

            Console.WriteLine("Input JSON: {0}", json);

​

            var unescapedJson = JsonExtensions.JsonPrettify(json, Formatting.None);

            Console.WriteLine("\nUnescaped JSON: {0}", unescapedJson);

            Console.WriteLine("\nUnescaping using System.Text.RegularExpressions.Regex.Unescape: ");

            Console.WriteLine(System.Text.RegularExpressions.Regex.Unescape(json));

        }   

    }

​

    public class Program

    {

        public static void Main()

        {

            Console.WriteLine("Environment version: " + Environment.Version);

            Console.WriteLine("Json.NET version: " + typeof(JsonSerializer).Assembly.FullName);

            Console.WriteLine();

​

            try

            {

                TestClass.Test();

            }

            catch (Exception ex)

            {

                Console.WriteLine("Failed with unhandled exception: ");

                Console.WriteLine(ex);

                throw;

            }

        }

    }

​