Book Image

C# 8.0 and .NET Core 3.0 – Modern Cross-Platform Development - Fourth Edition

By : Mark J. Price
Book Image

C# 8.0 and .NET Core 3.0 – Modern Cross-Platform Development - Fourth Edition

By: Mark J. Price

Overview of this book

In C# 8.0 and .NET Core 3.0 – Modern Cross-Platform Development, Fourth Edition, expert teacher Mark J. Price gives you everything you need to start programming C# applications. This latest edition uses the popular Visual Studio Code editor to work across all major operating systems. It is fully updated and expanded with new chapters on Content Management Systems (CMS) and machine learning with ML.NET. The book covers all the topics you need. Part 1 teaches the fundamentals of C#, including object-oriented programming, and new C# 8.0 features such as nullable reference types, simplified switch pattern matching, and default interface methods. Part 2 covers the .NET Standard APIs, such as managing and querying data, monitoring and improving performance, working with the filesystem, async streams, serialization, and encryption. Part 3 provides examples of cross-platform applications you can build and deploy, such as web apps using ASP.NET Core or mobile apps using Xamarin.Forms. The book introduces three technologies for building Windows desktop applications including Windows Forms, Windows Presentation Foundation (WPF), and Universal Windows Platform (UWP) apps, as well as web applications, web services, and mobile apps.
Table of Contents (21 chapters)

Consuming services using HTTP clients

Now that we have built and tested our Northwind service, we will learn how to call it from any .NET Core app using the HttpClient class and its new factory.

Understanding HttpClient

The easiest way to consume a web service is to use the HttpClient class. However, many people use it wrongly because it implements IDisposable and Microsoft's own documentation shows poor usage of it.

Usually when a type implements IDisposable you should create it inside a using statement to ensure that it is disposed as soon as possible. HttpClient is different because it is shared, reentrant, and partially thread safe.

More Information: It is the BaseAddress and DefaultRequestHeaders properties that you should treat with caution with multiple threads. You can read more details and recommendations at the following link:

The problem...