Joseph Albahari - C# 7.0 in a Nutshell: The Definitive Reference

by Joseph Albahari and Ben Albahari

Copyright 2018 Joseph Albahari, Ben Albahari. All rights reserved.

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• October 2017: First Edition

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C# 7.0 represents the sixth major update to Microsofts flagship programming language, positioning C# as a language with unusual flexibility and breadth. At one end, it offers high-level abstractions such as query expressions and asynchronous continuations, while at the other end, it allows low-level efficiency through constructs such as custom value types and optional pointers.

The price of this growth is that theres more than ever to learn. Although tools such as Microsofts IntelliSenseand online referencesare excellent in helping you on the job, they presume an existing map of conceptual knowledge. This book provides exactly that map of knowledge in a concise and unified stylefree of clutter and long introductions.

Like the past four editions, C# 7.0 in a Nutshell is organized around concepts and use cases, making it friendly both to sequential reading and to random browsing. It also plumbs significant depths while assuming only basic background knowledgemaking it accessible to intermediate as well as advanced readers.

This book covers C#, the CLR, and the core Framework assemblies. Weve chosen this focus to allow space for difficult topics such as concurrency, security, and application domainswithout compromising depth or readability. Features new to C# 6 and C# 7 and the associated Framework are flagged so that you can also use this book as a C# 5 and C# 6 reference.

Intended Audience

This book targets intermediate to advanced audiences. No prior knowledge of C# is required, but some general programming experience is necessary. For the beginner, this book complements, rather than replaces, a tutorial-style introduction to programming.

This book is an ideal companion to any of the vast array of books that focus on an applied technology such as ASP.NET, WPF, UWP, or WCF. The areas of the language and .NET Framework that such books omit, C# 7.0 in a Nutshell covers in detailand vice versa.

If youre looking for a book that skims every .NET Framework technology, this is not for you. This book is also unsuitable if you want to learn about APIs specific to mobile device development.

How This Book Is Organized

The first three chapters after the introduction concentrate purely on C#, starting with the basics of syntax, types, and variables, and finishing with advanced topics such as unsafe code and preprocessor directives. If youre new to the language, you should read these chapters sequentially.

The remaining chapters cover the core .NET Framework, including such topics as LINQ, XML, collections, concurrency, I/O and networking, memory management, reflection, dynamic programming, attributes, security, application domains, and native interoperability. You can read most of these chapters randomly, except for Chapters .

What You Need to Use This Book

The examples in this book require a C# 7.0 compiler and Microsoft .NET Framework 4.6/4.7. You will also find Microsofts .NET documentation useful to look up individual types and members (which is available online).

While its possible to write source code in Notepad and invoke the compiler from the command line, youll be much more productive with a code scratchpad for instantly testing code snippets, plus an Integrated Development Environment (IDE) for producing executables and libraries.

For a code scratchpad, download LINQPad 5 from www.linqpad.net (free). LINQPad fully supports C# 7.0 and is maintained by one of the authors.

For an IDE, download Microsoft Visual Studio 2017: any edition is suitable for whats taught in this book, except the free express edition.

Note

All , plus the chapters on concurrency, parallel programming, and dynamic programming are available as interactive (editable) LINQPad samples. You can download the whole lot in a single click: go to LINQPads Samples tab at the bottom left, click Download more samples, and choose C# 7.0 in a Nutshell.

Conventions Used in This Book

The . A slanted rectangle means an abstract class; a circle means an interface. A line with a hollow triangle denotes inheritance, with the triangle pointing to the base type. A line with an arrow denotes a one-way association; a line without an arrow denotes a two-way association.

Figure P-1. Sample diagram

The following typographical conventions are used in this book:

ItalicIndicates new terms, URIs, filenames, and directoriesConstant widthIndicates C# code, keywords and identifiers, and program outputConstant width boldShows a highlighted section of codeConstant width italicShows text that should be replaced with user-supplied values

Note

This icon signifies a tip, suggestion, or general note.

Warning

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Using Code Examples

This book is here to help you get your job done. In general, you may use the code in this book in your programs and documentation. You do not need to contact us for permission unless youre reproducing a significant portion of the code. For example, writing a program that uses several chunks of code from this book does not require permission. Selling or distributing a CD-ROM of examples from OReilly books