using System.Collections.Generic;
public static void Main()
string json = "{\"name\":\"tony\", \"age\":30}";
var dict = JsonSerializer.Deserialize<Dictionary<string, object>>(json);
dynamic result = new ExpandoObject();
var resultDict = (IDictionary<string, object>)result;
foreach (var kvp in dict)
resultDict[kvp.Key] = kvp.Value;
Console.WriteLine(result.name);
Console.WriteLine(result.age);