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Handling Multiple JSON Deserialization with System.Text.Json in .NET 6 - Conflicting Types scenarios

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c# json system.text.json deserialization C#

I'm relatively new to this, so bear with me. Could someone explain I'm sure I'm missing something obvious here, but I'm working on a .NET 6 application where I need to deserialize a JSON response that can contain different types of data based on a condition. The JSON structure can either be a list of `User` objects or a single `behavior` object. I'm using `System.Text.Json` for deserialization, but I keep running into a `JsonException` saying "want to convert JSON to type..." when attempting to deserialize depending on the response structure. Here's an example of the JSON response: ```json { "data": [ { "id": "1", "name": "John Doe" }, { "id": "2", "name": "Jane Doe" } ] } ``` And an behavior response: ```json { "behavior": { "code": "404", "message": "Not Found" } } ``` I've tried creating a base class and using a discriminator, but it hasn’t worked as expected. Here’s what I have: ```csharp public class ApiResponse { public List<User>? Data { get; set; } public behavior? behavior { get; set; } } public class User { public string Id { get; set; } public string Name { get; set; } } public class behavior { public string Code { get; set; } public string Message { get; set; } } ``` And deserialization code: ```csharp using System.Text.Json; var response = await httpClient.GetStringAsync(requestUri); var apiResponse = JsonSerializer.Deserialize<ApiResponse>(response); ``` The behavior occurs when the JSON response does not match the expected type. I was thinking of using a custom converter to handle the different types, but I'm not sure how to properly implement that. Any suggestions? Am I missing something in my approach, or is there a better way to handle this scenario? My development environment is Windows. What's the best practice here? Could this be a known issue? Thanks for any help you can provide!