// @nuget: Newtonsoft.Json

​

using System;

using System.IO;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        string testQuote = "testquote”";

        Console.WriteLine((int) testQuote[testQuote.Length-1]);

        using var stringWrt = new StringWriter();

        using (var s = new JsonTextWriter(stringWrt))

        {

            s.StringEscapeHandling = StringEscapeHandling.EscapeHtml;

            s.WriteStartObject();

            s.WritePropertyName("blah");

            s.WriteValue(testQuote);

            s.WriteEndObject();

        }

        var json = stringWrt.ToString();

        Console.WriteLine(json);

        Console.WriteLine((int) json[json.Length-3]);

    }

}