Hands-On RESTful Web Services with ASP.NET Core 3

The use of filters

As we mentioned previously, filters can have three different scopes: global, controller, and action. In the first case, the filter is applied globally in the Startup class. In the other two cases, the filter is used in the form of an attribute and is usually applied to the controller class definition or the action method definition. Let's take a closer look at these different approaches. The application of a filter in the Startup class means that the filter covers all the routes in the MVC pipeline, as follows:

    public class Startup    {        ...                public void ConfigureServices(IServiceCollection services)        {            services                .AddControllers(config => config.Filters.Add(new                  CustomFilter()));        }        ...    }

In this case, CustomFilter has a global ...