Update filter.md (dotnet#17036)

* Update filter.md

* Update aspnetcore/razor-pages/filter.md

Co-Authored-By: Artak <34246760+mkArtakMSFT@users.noreply.github.com>

Co-authored-by: Artak <34246760+mkArtakMSFT@users.noreply.github.com>

Author: Rick-Anderson

aspnetcore/razor-pages/filter.md

@@ -4,7 +4,7 @@ author: Rick-Anderson
 description: Learn how to create filter methods for Razor Pages in ASP.NET Core.
 monikerRange: '>= aspnetcore-2.1'
 ms.author: riande
-ms.date: 12/28/2019
+ms.date: 2/18/2020
 uid: razor-pages/filter
 ---
 # Filter methods for Razor Pages in ASP.NET Core
@@ -24,7 +24,7 @@ Razor Page filters:
 * Cannot be applied to specific page handler methods.
 * Can have constructor dependencies populated by [Dependency Injection](xref:fundamentals/dependency-injection) (DI). For more information, see [ServiceFilterAttribute](/aspnet/core/mvc/controllers/filters#servicefilterattribute) and [TypeFilterAttribute](/aspnet/core/mvc/controllers/filters#typefilterattribute).
 
-Code can be run before a handler method executes using the page constructor or middleware, but only Razor Page filters have access to <xref:Microsoft.AspNetCore.Mvc.RazorPages.PageModel.HttpContext>. Filters have a <xref:Microsoft.AspNetCore.Mvc.Filters.FilterContext> derived parameter, which provides access to `HttpContext`. For example, the [Implement a filter attribute](#ifa) sample adds a header to the response, something that can't be done with constructors or middleware.
+While page constructors and middleware enable executing custom code before a handler method executes, only Razor Page filters enable access to <xref:Microsoft.AspNetCore.Mvc.RazorPages.PageModel.HttpContext> and the page. Middleware has access to the `HttpContext`, but not to the "page context". Filters have a <xref:Microsoft.AspNetCore.Mvc.Filters.FilterContext> derived parameter, which provides access to `HttpContext`. For example, the [Implement a filter attribute](#ifa) sample adds a header to the response, something that can't be done with constructors or middleware.
 
 [View or download sample code](https://github.com/aspnet/AspNetCore.Docs/tree/master/aspnetcore/razor-pages/filter/3.1sample) ([how to download](xref:index#how-to-download-a-sample))