CORS in .NET Core

Question

I am trying to enable CORS in .NET Core in this way:

    public IConfigurationRoot Configuration { get; }

    public void ConfigureServices(IServiceCollecti         


        

Answer 1

I encountered CORS issues in my application. I felt that I properly implemented the logic but was still getting presented with Access-Control-Allow-Origin 403 Error. I tried every setting mentioned above but nothing worked.

I later discovered that my issue wasn't CORS related. I implemented a custom attribute

[Route("v1/[Controller]")]
[ServiceFilter(typeof(MyCustomFilterAttribute))]
public class MySpecialListsController 

Calls made to the controller were properly making it to the method OnActionExecuting

public override void OnActionExecuting(ActionExecutingContext context)

The logic within the filter was throwing an exception and was presented as a CORS 403 error.