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)

Writing LINQ queries

Although we wrote a few LINQ queries in Chapter 11, Working with Databases Using Entity Framework Core, they weren't the focus, and so I didn't properly explain how LINQ works, but let's now take time to properly understand them.

LINQ has several parts; some are required, and some are optional:

  • Extension methods (required): These include examples such as Where, OrderBy, and Select. These are what provide the functionality of LINQ.
  • LINQ providers (required): These include LINQ to Objects, LINQ to Entities, LINQ to XML, LINQ to OData, and LINQ to Amazon. These are what convert standard LINQ operations into specific commands for different types of data.
  • Lambda expressions (optional): These can be used instead of named methods to simplify LINQ extension method calls.
  • LINQ query comprehension syntax (optional): These include from, in, where, orderby, descending, and select. These are C# keywords that are aliases for some of the...