using System;

using System.Collections.Generic;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        var dict = new Dictionary<string, string>();

        dict.Add("eventName", "hello");

​

        string json = JsonConvert.SerializeObject(dict, Formatting.Indented);

        Console.WriteLine(json);

    }

}

​

​