Book Image

C# 9 and .NET 5 – Modern Cross-Platform Development - Fifth Edition

By : Mark J. Price
Book Image

C# 9 and .NET 5 – Modern Cross-Platform Development - Fifth Edition

By: Mark J. Price

Overview of this book

In C# 9 and .NET 5 – Modern Cross-Platform Development, Fifth 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 a new chapter on the Microsoft Blazor framework. The book’s first part teaches the fundamentals of C#, including object-oriented programming and new C# 9 features such as top-level programs, target-typed new object instantiation, and immutable types using the record keyword. Part 2 covers the .NET APIs, for performing tasks like managing and querying data, monitoring and improving performance, and working with the file system, async streams, serialization, and encryption. Part 3 provides examples of cross-platform apps you can build and deploy, such as websites and services using ASP.NET Core or mobile apps using Xamarin.Forms. The best type of application for learning the C# language constructs and many of the .NET libraries is one that does not distract with unnecessary application code. For that reason, the C# and .NET topics covered in Chapters 1 to 13 feature console applications. In Chapters 14 to 20, having mastered the basics of the language and libraries, you will build practical applications using ASP.NET Core, Model-View-Controller (MVC), and Blazor. By the end of the book, you will have acquired the understanding and skills you need to use C# 9 and .NET 5 to create websites, services, and mobile apps.
Table of Contents (23 chapters)
22
Index

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...