static void Main(string[] args) { Ticket tick1 = new Ticket(1, "09-04-2020", 1, "A", 15); Ticket tick2 = new Ticket(1, "09-04-2020", 1, "A", 16); Ticket tick3 = new Ticket(1, "09-04-2020", 1, "A", 17); JsonSerializerOptions options = new JsonSerializerOptions { WriteIndented = true, IgnoreNullValues = true, IgnoreReadOnlyProperties = true }; //STORE JSON OBJECT var jsonString = JsonSerializer.Serialize(new Ticket[] { tick1, tick2, tick3 }, options); Console.WriteLine(jsonString); File.WriteAllText("data.json", jsonString); //READ AND UPDATE JSON OBJECT string jsonText = File.ReadAllText("data.json"); List <Ticket> tickets = new List <Ticket>(); using (JsonDocument document = JsonDocument.Parse(jsonString)) { JsonElement root = document.RootElement; JsonElement ticketsArrayElement = root; foreach (JsonElement ticket in ticketsArrayElement.EnumerateArray()) { //Make .NET object is values are present in JSON if (ticket.TryGetProperty("Price", out JsonElement PriceElement) && ticket.TryGetProperty("Date", out JsonElement DateElement) && ticket.TryGetProperty("TheaterNumber", out JsonElement TheaterElement) && ticket.TryGetProperty("SeatNumber", out JsonElement SeatElement) && SeatElement.TryGetProperty("Row", out var RowElement) && SeatElement.TryGetProperty("Seat", out var SeatNumElement) ) { int price = PriceElement.GetInt32(); string date = DateElement.GetString(); int theaterNumber = TheaterElement.GetInt32(); string row = RowElement.GetString(); int seat = SeatNumElement.GetInt32(); tickets.Add(new Ticket(price, date, theaterNumber, row, seat)); } } } tickets[0].Date = "DATE HAS BEEN MODIFIED"; jsonText = JsonSerializer.Serialize(tickets, options); File.WriteAllText("data.json", jsonText); }