Joseph Albahari - C# 6.0 in a Nutshell

by Joseph Albahari and Ben Albahari

Copyright 2016 Joseph Albahari and Ben Albahari. All rights reserved.

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• December 2015: Sixth Edition

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C# 6.0 represents the fifth 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 the optional use of 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 three editions, C# 6.0 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# 6.0 and the associated Framework are flagged so that you can also use this book as a C# 5.0 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.

If youre already familiar with C# 5.0, youll find updated language sections, and a new chapter on Roslyn, the compiler-as-a-service.

This book is an ideal companion to any of the vast array of books that focus on an applied technology such as WPF, ASP.NET, or WCF. The areas of the language and .NET Framework that such books omit, C# 6.0 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 tablet or Windows Phone 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, code contracts, 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# 6.0 compiler and Microsoft .NET Framework 4.6. 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 or later from http://www.linqpad.net (free). LINQPad fully supports C# 6.0 and is maintained by one of the authors.

For an IDE, download Microsoft Visual Studio 2015: any edition, except the free express edition, is suitable for whats taught in this book.

Note

and choose C# 6.0 in a Nutshell.

Conventions Used in This Book

. 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:

Italic

Indicates new terms, URIs, filenames, and directories

Constant width

Indicates C# code, keywords and identifiers, and program output

Constant width bold

Shows a highlighted section of code

Constant width italic

Shows text that should be replaced with user-supplied values

Tip

This element signifies a tip or suggestion.

Note

This element signifies a general note.

Warning

This element indicates a warning or caution.

Using Code Examples

Supplemental material (code examples, exercises, etc.) is available for download at LINQPads Sample Libraries page: choose C# 6.0 in a Nutshell.

This book is here to help you get your job done. In general, if example code is offered with this book, you may use it 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 does require permission. Answering a question by citing this book and quoting example code does not require permission. Incorporating a significant amount of example code from this book into your products documentation does require permission.