为什么我的 GlobalExceptionFilter 在 NET.Core 上不起作用？

Question

I'm trying to implement GlobalExceptionFilter in NET Core WEB API. This my filter code:

public class GlobalExceptionFilter : IExceptionFilter, IDisposable
{
    private readonly ILogger _logger;
    public GlobalExceptionFilter(ILoggerFactory logger)
    {
        if (logger == null)
        {
            throw new ArgumentNullException(nameof(logger));
        }

        this._logger = logger.CreateLogger("Global Exception Filter");
    }

    public void Dispose()
    {
    }

    public void OnException(ExceptionContext context)
    {
        Dictionary<string, string> data = new Dictionary<string, string>();
        HttpStatusCode statusCode = HttpStatusCode.InternalServerError;
        String message = String.Empty;

        var ex = context.Exception;

        TypeSwitch.Do(ex,
                TypeSwitch.Case<ArgumentException>(() => { statusCode = HttpStatusCode.BadRequest; }),
                TypeSwitch.Case<ArgumentNullException>(() => { statusCode = HttpStatusCode.BadRequest; }),
                TypeSwitch.Case<ArgumentOutOfRangeException>(() => { statusCode = HttpStatusCode.BadRequest; }),
                TypeSwitch.Case<KeyNotFoundException>(() => { statusCode = HttpStatusCode.NotFound; }),
                TypeSwitch.Case<DivideByZeroException>(() => { statusCode = HttpStatusCode.MethodNotAllowed; }),
                TypeSwitch.Case<QueryFormatException>(() => { statusCode = HttpStatusCode.MethodNotAllowed; })
            );

        HttpResponse response = context.HttpContext.Response;
        response.StatusCode = (int)statusCode;
        response.ContentType = "application/json";
        var err = new ErrorPayload()
        {
            Data = data,
            StackTrace = ex.StackTrace,
            Message = ex.Message,
            StatusCode = (int)statusCode
        };
        response.WriteAsync(JsonConvert.SerializeObject(err));
    }
}

This is my initializing code in

public void ConfigureServices(IServiceCollection services)
{
    services.AddApplicationInsightsTelemetry(Configuration);
    services.AddMvc( config =>
        {
            config.Filters.Add(typeof(GlobalExceptionFilter));                    
        }
    );
}

And i'm testing the error handling in this controller method

[HttpGet("{idCliente}")]
public IActionResult GetCliente(int idCliente)
{
    throw new QueryFormatException("My Custom Exception");
}

Any ideas? thanks!

UPDATE

Well, I have to admit that I asume that wasn't working because Postman shows me connection error instead of MethodNotAllowed of NotFound (404). As suggested i examine the debug and the status response and was actually expected value.

Answer 1

As the docs say (last section)

Prefer middleware for exception handling. Use exception filters only where you need to do error handling differently based on which MVC action was chosen. For example, your app might have action methods for both API endpoints and for views/HTML. The API endpoints could return error information as JSON, while the view-based actions could return an error page as HTML.

In your case, if the application only serving API:s then use the exception middleware implementation instead. Here's a good example of one