Although much of C# 4.0 is still virtually the same as the previous version, this new version adds some exciting new features, most of which revolve around COM Interop, to assist with Office development. The big new additions that this book covers include these topics:

Leaving aside a few of the more esoteric and advanced additions, we mention a few smaller items here and there as appropriate. (Don't worry if parts of this introduction are Geek to you. You'll get there.)

Because the features of C# 4.0 all tie together for use in a single major operation — COM Interop — we bundled discussions of these features in the back of this book, in Book VIII. Throughout this book, we have updated chapters from the original C# 3.0 material wherever it seemed appropriate.

The goal of this book is to explain C# to you. To write usable programs, you need a specific coding environment. We're betting that most readers will use Microsoft Visual Studio, although we suggest alternatives. Because this book is an All-in-One, we give you comprehensive coverage of Visual Studio in Book IV.

The original version of C# For Dummies (like all programming language books) focused on C# as a language, not all of the things you do with C#. This version of the book — in the mondo-size All-in-One format — covers Windows development, Web development, service development, and .NET Framework development, such as graphics and databases.

Our goal is to make a one-stop shop for development with Microsoft products, though there is indeed more to the topics than fits in this book. Office development isn't covered, for instance. SharePoint has way too much going on to cover it along with everything else (although Bill co-authored VSTO For Dummies). This book is designed to handle the vast majority of C# users, though 20 percent of our readers will be working on something that we don't cover. Sorry about that — we'll try to stretch the book to 1,000 pages next time.

Another point is that every programming problem is different. Although many different situations are covered between the covers of this book, your specific situation is different. Some interpolation has to be taking place. If you have a question about how your personal situation fits in, send the author an e-mail at csharpfordummies.net and we'll try to help.

You need, at minimum, the .NET Common Language Runtime (CLR) before you can even execute the programs generated by C#. Visual Studio 2010 copies the CLR onto your machine as part of its installation procedure. Alternatively, you can download the entire .NET package, including the C# compiler and many other useful tools, from the Microsoft Web site at msdn.microsoft.com. Look for the .NET Software Development Kit (SDK). The book's Web site at csharpfordummies.net explains how to get these items.

We've made this book as easy to use as possible. Figuring out a new language is hard enough — why make it any more complicated than it needs to be? Though this book is divided into eight minibooks, we use an even easier subdivision.

Books I and II comprise the bulk of the original C# For Dummies book, and they cover the C# language, updated for version 4.0. Books III and IV cover technologies that are peripheral to C#. Books V, VI, and VII cover the three main types of development you do in C# — Windows Presentation Foundation, Web development, and service-oriented programming. We finish with the (thankfully short) Book VIII, about new C# 4.0 features.

If you're brand new, start at the beginning and read the first two minibooks. You'll discover a lot. Really. It will seem as though you're reading a lot of text, but it is engaging and has interesting examples.

If you're using the .NET Framework (which you probably are), read Book III as well. If you're using Visual Studio, read Book IV. (Note that we use Visual Studio 2010 Professional edition, so if you're using Express or Ultimate, your screens might look slightly different.)

Finally, you can focus on your project type — Books V, VI, and VII are specific to project type, and you can pick and choose what to read. These three minibooks are organized more as a collection of related articles than as discrete book units. You'll find them easier to use that way.

Here's a brief rundown of what you'll find in each part of this book.

Throughout the pages of this book, we use the following icons to highlight important information:

Throughout this book, we use several conventions to help you get your bearings. Terms that aren't "real words," such as the names of program variables, appear in this font to minimize confusion. Program listings are offset from the text this way:

use System;
namespace MyNameSpace
{
  public class MyClass
  {
  }
}

Each listing is followed by a clever, insightful explanation. Complete programs are included on the Web site for your viewing pleasure; small code segments are not.

When you see a command arrow, as in the instruction "Choose File

Obviously, your first step is to figure out the C# language — ideally, by using C# 2010 All-in-One For Dummies, of course. You may want to give yourself a few months of practice in writing simple C# programs before taking the next step of discovering how to create graphical Windows applications. Give yourself many months of Windows application experience before you branch out into writing programs intended to be distributed over the Internet.

In the meantime, you can keep up with C# goings and comings in several locations. First, check out the official source: msdn.microsoft.com/msdn. In addition, various programmer Web sites have extensive material on C#, including lively discussions all the way from how to save a source file to the relative merits of deterministic versus nondeterministic garbage collection. (Around Bill's house, garbage collection is quite deterministic: It's every Wednesday morning.) Here's a description of a few large C# sites: