[c#] How to return HTTP 500 from ASP.NET Core RC2 Web Api?

Back in RC1, I would do this:

public IActionResult Post([FromBody]string something)
        // ...
    catch(Exception e)
         return new HttpStatusCodeResult((int)HttpStatusCode.InternalServerError);

In RC2, there no longer is HttpStatusCodeResult, and there is nothing I can find that lets me return a 500 type of IActionResult.

Is the approach now entirely different for what I'm asking? Do we no longer try-catch in Controller code? Do we just let the framework throw a generic 500 exception back to the API caller? For development, how can I see the exact exception stack?

This question is related to c# asp.net-core asp.net-core-mvc

The answer is

A better way to handle this as of now (1.1) is to do this in Startup.cs's Configure():


This will execute the route for /Error. This will save you from adding try-catch blocks to every action you write.

Of course, you'll need to add an ErrorController similar to this:

public class ErrorController : Controller
    public IActionResult Get()
        return StatusCode(StatusCodes.Status500InternalServerError);

More information here.

In case you want to get the actual exception data, you may add this to the above Get() right before the return statement.

// Get the details of the exception that occurred
var exceptionFeature = HttpContext.Features.Get<IExceptionHandlerPathFeature>();

if (exceptionFeature != null)
    // Get which route the exception occurred at
    string routeWhereExceptionOccurred = exceptionFeature.Path;

    // Get the exception that occurred
    Exception exceptionThatOccurred = exceptionFeature.Error;

    // TODO: Do something with the exception
    // Log it with Serilog?
    // Send an e-mail, text, fax, or carrier pidgeon?  Maybe all of the above?
    // Whatever you do, be careful to catch any exceptions, otherwise you'll end up with a blank page and throwing a 500

Above snippet taken from Scott Sauber's blog.

For aspnetcore-3.1, you can also use Problem() like below;


public IActionResult ErrorLocalDevelopment(
    [FromServices] IWebHostEnvironment webHostEnvironment)
    if (webHostEnvironment.EnvironmentName != "Development")
        throw new InvalidOperationException(
            "This shouldn't be invoked in non-development environments.");

    var context = HttpContext.Features.Get<IExceptionHandlerFeature>();

    return Problem(
        detail: context.Error.StackTrace,
        title: context.Error.Message);

When you want to return a JSON response in MVC .Net Core You can also use:

Response.StatusCode = (int)HttpStatusCode.InternalServerError;//Equals to HTTPResponse 500
return Json(new { responseText = "my error" });

This will return both JSON result and HTTPStatus. I use it for returning results to jQuery.ajax().

How about creating a custom ObjectResult class that represents an Internal Server Error like the one for OkObjectResult? You can put a simple method in your own base class so that you can easily generate the InternalServerError and return it just like you do Ok() or BadRequest().

public class MyController : MyControllerBase
    public IActionResult Get(int key)
            //do something that fails
        catch (Exception e)
            return InternalServerError();

public class MyControllerBase : ControllerBase
    public InternalServerErrorObjectResult InternalServerError()
        return new InternalServerErrorObjectResult();

    public InternalServerErrorObjectResult InternalServerError(object value)
        return new InternalServerErrorObjectResult(value);

public class InternalServerErrorObjectResult : ObjectResult
    public InternalServerErrorObjectResult(object value) : base(value)
        StatusCode = StatusCodes.Status500InternalServerError;

    public InternalServerErrorObjectResult() : this(null)
        StatusCode = StatusCodes.Status500InternalServerError;

return StatusCode((int)HttpStatusCode.InternalServerError, e);

Should be used in non-ASP.NET contexts (see other answers for ASP.NET Core).

HttpStatusCode is an enumeration in System.Net.

If you need a body in your response, you can call

return StatusCode(StatusCodes.Status500InternalServerError, responseObject);

This will return a 500 with the response object...

You could use Microsoft.AspNetCore.Mvc.ControllerBase.StatusCode and Microsoft.AspNetCore.Http.StatusCodes to form your response, if you don't wish to hardcode specific numbers.

return  StatusCode(StatusCodes.Status500InternalServerError);

UPDATE: Aug 2019

Perhaps not directly related to the original question but when trying to achieve the same result with Microsoft Azure Functions I found that I had to construct a new StatusCodeResult object found in the Microsoft.AspNetCore.Mvc.Core assembly. My code now looks like this;

return new StatusCodeResult(StatusCodes.Status500InternalServerError);

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