What’s New in the 4th Edition

The 4th Edition is an almost complete reimagining of The C# Player’s Guide. I didn’t intend on such a significant rework when I started, but it’s where I ended up at. I sometimes feel like I literally rewrote the book twice in this process. There is hardly a sentence that didn’t get touched, and many chapters got a complete rewrite.

Yet the book is the same book at its heart. Or maybe you could say that the 4th Edition is finally what I had hoped the 1st Edition would be, and it has just taken until now for it to finally get here.

The major new features are these:

• Reimagined the book to be better aligned with the idea of it being a player’s guide, and that the game to play is programming and learning to program.
  • In a Nutshell sections are now Speedrun sections.
  • Try It Out! sections are now Challenge sections.
  • Quiz sections are now Knowledge Check sections.
  • Some sections are now Side Quests, which mark a section as something reasonably safe to skip.
  • Chapters are now called Levels.
  • Lots of additional challenges were added, and they form a loose storyline/plot for new programmers to follow.
  • By completing challenges, you now gain XP, which you can track as you go through the book.
• I tried to flatten out the learning curve around object-oriented design a bit better. The book isn’t specifically about design, but it is important for people to understand the basics to be able to do things in C#. So the book contains more information about how to break a large program into smaller parts and then combine those parts to form the final solution.
• New website focused on just this book, cutting out other clutter (you’re here).
• Updated to C# 9:
  • Top-level statements - the book fully embraces this new model throughout the book and solutions.
  • New pattern tools - added to the Patterns chapter, which was completely rewritten:
    • Parenthesized patterns.
    • Comparison patterns (>=, <=, >, and <).
    • and, or, and not patterns.
  • init accessors - added to the properties chapter, used by records.
  • Records - added a whole new chapter.
  • Covariant return types (you can now override a method with a more specific return type) - added to the polymorphism chapter.
  • Native integer types (nint and nuint) - added a small section in the Unsafe Code chapter.
  • Using static to disallow capturing variables - added to the section talking about closures.
  • Using just plain new () in cases where the type can be inferred - called out in the book, though most of the book still explicitly names types (a similar argument for why the book uses var).
  • Partial methods are now much more flexible - the section about partial methods and classes got completely rewritten, but it is a small section in the back of the book.
  • A handful of other small things.
• Updated to .NET 5. 3rd Edition was focused on .NET Framework, but the .NET world has changed substantially in the last few years. Everybody who can should be using .NET 5 (the evolution of .NET Core) whenever possible now (and if not, then .NET Core 3.1, and only use other stuff when necessary).
• More emphasis on other IDEs aside from Visual Studio. Visual Studio is still central, but Visual Studio Code got a lot more love in this version.
• Lots of other stuff to improve clarity and fix typos throughout the book.