Unexpected NullReferenceException When Accessing Properties of a Dynamic Object in .NET 6
I'm trying to debug I'm working with a `NullReferenceException` when trying to access properties of a dynamic object in my .NET 6 application... The scenario arises when I'm working with a JSON response from an API, which I need to deserialize into a dynamic type. My code looks something like this: ```csharp using System; using System.Net.Http; using System.Threading.Tasks; using Newtonsoft.Json; public class ApiService { private readonly HttpClient _httpClient; public ApiService(HttpClient httpClient) { _httpClient = httpClient; } public async Task<string> GetUserNameAsync(int userId) { var response = await _httpClient.GetStringAsync($"https://api.example.com/users/{userId}"); dynamic user = JsonConvert.DeserializeObject(response); // This line throws NullReferenceException return user.username; } } ``` When I call `GetUserNameAsync(1)`, I get a `NullReferenceException` on the line where I try to access `user.username`. The JSON response I expect is: ```json { "id": 1, "username": "john_doe" } ``` However, sometimes the API returns a response without the `username` field—either because the user doesn't have a username set or due to a transient behavior. I've tried adding checks for existence before accessing the `username`, like this: ```csharp if (user.username != null) { return user.username; } ``` But it still throws the same exception. I also considered using a strongly typed model instead of a dynamic type, but I want to keep it flexible for other API responses. How can I handle this more gracefully and avoid the `NullReferenceException`? Is there a better way to work with dynamic objects in this scenario? Also, would switching to a strongly typed object help mitigate these issues in the long run? Any insights would be appreciated!