Book Image

ASP.NET Core MVC 2.0 Cookbook

By : Jason De Oliveira, Engin Polat, Stephane Belkheraz
Book Image

ASP.NET Core MVC 2.0 Cookbook

By: Jason De Oliveira, Engin Polat, Stephane Belkheraz

Overview of this book

The ASP.NET Core 2.0 Framework has been designed to meet all the needs of today’s web developers. It provides better control, support for test-driven development, and cleaner code. Moreover, it’s lightweight and allows you to run apps on Windows, OSX and Linux, making it the most popular web framework with modern day developers. This book takes a unique approach to web development, using real-world examples to guide you through problems with ASP.NET Core 2.0 web applications. It covers Visual Studio 2017- and ASP.NET Core 2.0-specifc changes and provides general MVC development recipes. It explores setting up .NET Core, Visual Studio 2017, Node.js modules, and NuGet. Next, it shows you how to work with Inversion of Control data pattern and caching. We explore everyday ASP.NET Core MVC 2.0 patterns and go beyond it into troubleshooting. Finally, we lead you through migrating, hosting, and deploying your code. By the end of the book, you’ll not only have explored every aspect of ASP.NET Core MVC 2.0, you’ll also have a reference you can keep coming back to whenever you need to get the job done.
Table of Contents (26 chapters)
Title Page
Copyright and Credits
Packt Upsell
Contributors
Preface
Index

Understanding and using a value provider


In this recipe, you will learn what a value provider is, and how to use it.

Getting ready

We will create an ASP.NET Core MVC Web Application template by going to File | New | Project | AspNet Core Web Application (.Net Framework) | Web Application.

How to do it...

The ASP.NET ModelBinding mechanism maps action method parameters to value providers. Value providers can be form data, route data, QueryString, and Files. They can be any data sent through an HTTP request, but not exclusively.

An interesting case to create a custom value provider could be creating a value provider for HTTP headers, cookie values, and so on; however, we could also create a ValueProvider class to retrieve AppSettings, or ConnectionString settings.

  1. Let's start by creating a ValueProvider class that inherits from IValueProvider. This class will implement two methods from IValueProvider:
    • bool ContainsPrefix(string prefix), this method tells us whether the ValueProvider is able to return...