Book Image

Learn C# Programming

By : Marius Bancila, Raffaele Rialdi, Ankit Sharma
5 (1)
Book Image

Learn C# Programming

5 (1)
By: Marius Bancila, Raffaele Rialdi, Ankit Sharma

Overview of this book

The C# programming language is often developers’ primary choice for creating a wide range of applications for desktop, cloud, and mobile. In nearly two decades of its existence, C# has evolved from a general-purpose, object-oriented language to a multi-paradigm language with impressive features. This book will take you through C# from the ground up in a step-by-step manner. You'll start with the building blocks of C#, which include basic data types, variables, strings, arrays, operators, control statements, and loops. Once comfortable with the basics, you'll then progress to learning object-oriented programming concepts such as classes and structures, objects, interfaces, and abstraction. Generics, functional programming, dynamic, and asynchronous programming are covered in detail. This book also takes you through regular expressions, reflection, memory management, pattern matching, exceptions, and many other advanced topics. As you advance, you'll explore the .NET Core 3 framework and learn how to use the dotnet command-line interface (CLI), consume NuGet packages, develop for Linux, and migrate apps built with .NET Framework. Finally, you'll understand how to run unit tests with the Microsoft unit testing frameworks available in Visual Studio. By the end of this book, you’ll be well-versed with the essentials of the C# language and be ready to start creating apps with it.
Table of Contents (20 chapters)

Pattern matching

Pattern matching is the process of checking whether a value has a particular shape as well as extracting information out of the value when the matching is successful. To some extent, that is what we regularly do with the if and switch statements when we check whether an object has some value and then proceed to extract information from it. However, this is a rudimentary form of pattern matching.

In C# 7, new capabilities are added to is and switch statements to enable pattern matching capabilities that drive a better separation of data and code and lead to more concise and readable code. The pattern matching capabilities are extended with new features in C# 8. You will learn about these in Chapter 15, New Features of C# 8.

The is expression

At runtime, the is operator checks that an object is compatible with a given type (the general form, expr is type). However, in C# 7, this was extended to include several forms of pattern matching:

  • Type pattern...