using System; using System.Json; public class Example { public static void Main() { JsonObject obj = new JsonObject(); JsonArray array = new JsonArray { 1, 2, 3 }; obj.Add("numbers", array); Console.WriteLine(obj.ToString()); } }In this code example, we create a new JsonObject, and then we create a JsonArray that contains the values 1, 2, and 3. Then we add the array to the JsonObject using the Add method. Finally, we print the JsonObject as a string to the console. The package library for this method is System.Json.