Book Image

Modern Web Development with ASP.NET Core 3 - Second Edition

By : Ricardo Peres
Book Image

Modern Web Development with ASP.NET Core 3 - Second Edition

By: Ricardo Peres

Overview of this book

ASP.NET has been the preferred choice of web developers for a long time. With ASP.NET Core 3, Microsoft has made internal changes to the framework along with introducing new additions that will change the way you approach web development. This second edition has been thoroughly updated to help you make the most of the latest features in the framework, right from gRPC and conventions to Blazor, which has a new chapter dedicated to it. You’ll begin with an overview of the essential topics, exploring the Model-View-Controller (MVC) pattern, various platforms, dependencies, and frameworks. Next, you’ll learn how to set up and configure the MVC environment, before delving into advanced routing options. As you advance, you’ll get to grips with controllers and actions to process requests, and later understand how to create HTML inputs for models. Moving on, you'll discover the essential aspects of syntax and processes when working with Razor. You'll also get up to speed with client-side development and explore the testing, logging, scalability, and security aspects of ASP.NET Core. Finally, you'll learn how to deploy ASP.NET Core to several environments, such as Azure, Amazon Web Services (AWS), and Docker. By the end of the book, you’ll be well versed in development in ASP.NET Core and will have a deep understanding of how to interact with the framework and work cross-platform.
Table of Contents (26 chapters)
Section 1: The Fundamentals of ASP.NET Core 3
Section 2: Improving Productivity
Section 3: Advanced Topics
Appendix A: The dotnet Tool

Understanding action filters

Action filters are invoked before and after an action method is called, so they can be used, for example, to do the following:

  • Cache results
  • Modify parameters
  • Modify results

Now, we already have the parameters to the action method, which come from the value providers. Here, the filter interfaces are IActionFilter and IAsyncActionFilter. The synchronous one offers two methods, OnActionExecuting and OnActionExecuted. They are for pre-event and post-event notifications. OnActionExecuting takes a single parameter of the ActionExecutingContext type, offering the following properties:

  • Result (IActionResult): Set a value here to short-circuit the request processing pipeline and return a value to the client, without actually executing the action.
  • ActionArguments (IDictionary<string, object>): The parameters of the action method.
  • Controller...