Introduction

If we were to describe the C# language and its associated environment, the .NET Framework, as the most important new technology for developers for many years, we would not be exaggerating. .NET is designed to provide a new environment within which you can develop almost any application to run on Windows, while C# is a new programming language that has been designed specifically to work with .NET. Using C# you can, for example, write a dynamic Web page, an XML Web service, a component of a distributed application, a database access component, a classic Windows desktop application, or even a new smart client application that allows for online/offline capabilities. This book covers the .NET Framework 2.0 and the newly released .NET Framework 3.0. If you are coding using version 1.0, 1.1, or just 2.0, there may be sections of the book that will not work for you. We try to notify you of items that are new to the .NET Framework 3.0 specifically.

Don’t be fooled by the .NET label. The NET bit in the name is there to emphasize Microsoft’s belief that distributed applications, in which the processing is distributed between client and server, are the way forward, but C# is not just a language for writing Internet or network-aware applications. It provides a means for you to code up almost any type of software or component that you might need to write for the Windows platform. Between them, C# and .NET are set both to revolutionize the way that you write programs, and to make programming on Windows much easier than it has ever been.

That’s quite a substantial claim, and it needs to be justified. After all, we all know how quickly computer technology changes. Every year Microsoft brings out new software, programming tools, or versions of Windows, with the claim that these will be hugely beneficial to developers. So what’s different about .NET and C#?

Introduction

C# is a relatively new language that was unveiled to the world when Microsoft released the first version of its .NET Framework. Since then its popularity has rocketed, and it has arguably become the language of choice for both Windows and Web developers who use .NET. Part of the appeal of C# comes from its clear syntax, which derives from C/C++, but simplifies some things that have previously discouraged some programmers. Despite this simplification, C# has retained the power of C++, and there is now no reason not to move into C#. The language is not difficult, and is an excellent one to learn elementary programming techniques with. This ease of learning, combined with the capabilities of the .NET Framework, make C# an excellent way to start your programming career.

The latest release of C#, part of .NET 2.0, builds on the existing successes and adds even more attractive features. Some of these, again, have their roots in C++—at least superficially—but some are entirely new. The latest release of Visual Studio also brings many tweaks and improvements to make your life easier and dramatically increase your productivity.

This book is intended to teach you about all aspects of C# programming, from the language itself, through Windows and Web programming, to making use of data sources, and finally to some advanced techniques such as graphics programming. You'll also learn about the capabilities of Visual Studio 2005 and all the ways that it can aid your application development. The book is written in a friendly, mentor-style fashion, where each chapter builds on previous ones and every effort is made to ease you into advanced techniques painlessly. At no point will technical terms appear from nowhere to discourage you from continuing; every concept is introduced and discussed as required. Technical jargon is kept to a minimum, but where it is necessary, it too will be properly defined and laid out in context.

The authors of this book are all experts in their field, and are all enthusiastic in their passion for both the C# language and the .NET Framework. Nowhere will you find a group of people better qualified to take you under their collective wing and nurture your understanding of C# from first principles to advanced techniques. Along with the fundamental knowledge it provides, this book is packed full of helpful hints, tips, exercises, and fully-fledged example code (available for download at p2p.wrox.com) that you will find yourself using time and again as your career progresses.

We pass this knowledge on without begrudging it, and hope that you will be able to use it to become the best programmer you can be. Good luck, and all the best!

Introduction   

Over the past 25 years I ’ ve written 15 books on various programming topics. You might wonder why so many  . . .  Didn ’ t I get it right the first time? Well, no, I didn ’ t  . . .  not really. When I wrote my first book over 25 years ago, object - oriented programming (OOP) was obscure at best and unknown to most. Like so many others, I had to go through the OOP learning process before I could appreciate what OOP was all about. I have a feeling that there are a lot of people out there who still feel that way.  Each time I teach a programming class, I learn new and better ways to explain things. When I look out across a classroom filled with students and it looks like a still - life painting, it ’ s time to back off, retool, and try a different approach to whatever concept it is I ’ m trying to teach. Every class I ’ ve taught has offered new perspectives on how I teach and how students learn. Changing my examples and the techniques I use to teach programming concepts is one of the reasons I came back to teaching after so many years away  . . .  I missed the learning experience.

A number of the books I wrote were concerned with languages other than C#, but that too provides for an enriching experience for me as an instructor. The strengths and weaknesses of a language can be appreciated only if you ’ ve grappled with some other less - than - perfect languages. The fact that programming languages continue to evolve supports the conclusion that I ’ m not the only one who is still learning. After all this time, the one thing that I have learned with absolute certainty is that whatever I know today will likely be out of date tomorrow.

Introduction

I remember a time years ago when I proposed a book to Apress regarding a forthcoming software SDK code-named Next Generation Windows Services (NGWS). As you may be aware, NGWS eventu- ally became what we now know as the .NET platform. My research of the C# programming language and the .NET platform took place in parallel with the authoring of the initial manuscript. It was a fantastic project; however, I must confess that it was more than a bit nerve-racking writing about a technology that was undergoing drastic changes over the course of its development. Thankfully, after many sleepless nights, the first edition of C# and the .NET Platformwas published in conjunc-tion with the release of .NET 1.0 Beta 2, circa the summer of 2001.

Since that point, I have been extremely happy and grateful to see that this text was very well received by the press and, most important, by readers. Over the years it was nominated as a Jolt Award finalist (I lost . . . crap!) and for the 2003 Referenceware Excellence Award in the program-ming book category (I won? Cool!).

The second edition of this text (C# and the .NET Platform, Second Edition) provided me the opportunity to expand upon the existing content with regard to version 1.1 of the .NET platform. Although the second edition of the book did offer a number of new topics, a number of chapters and examples were unable to make it into the final product.

Once the text entered its third edition (Pro C# 2005 and the .NET 2.0 Platform), the manuscript was updated to account for the numerous bells and whistles brought about by .NET 2.0 (new C# programming constructs, generics, updates to core APIs, etc.), and it included new material that had long been written but not yet published (such as content on the common intermediate lan- guage [CIL] and dynamic assemblies, and expanded ASP.NET coverage).

In this special edition of the text, I have added six new chapters dedicated to the new pro-gramming APIs brought about with the release of .NET 3.0. Over these chapters, you will come to understand the role of Windows Presentation Foundation (WPF), Windows Communication Foundation (WCF), and Windows Workflow Foundation (WF). As well, this new text provides details regarding the forthcoming C# 3.0 programming language and LINQ programming technologies (LINQ to SQL and LINQ to XML). While C# 3.0 and LINQ are currently beta technologies, the final two chapters of this text will provide a solid road map for the changes to come.

As with the earlier editions, this special edition presents the C# programming language and .NET base class libraries using a friendly and approachable tone. I have never understood the need some technical authors have to spit out prose that reads more like a GRE vocabulary study guide than a readable book. As well, this new edition remains focused on providing you with the informa- tion you need to build software solutions today, rather than spending too much time examining esoteric details that few individuals will ever actually care about.

Introduction

This book has existed (in one form or another) since the first edition of C# and the .NET Platform was published in conjunction with the release of .NET 1.0 Beta 2, circa the summer of 2001. Since that point, I have been extremely happy and grateful to see that this text was very well received by the press and, most important, by readers. Over the years it was nominated as a Jolt Award finalist (I lost . . . crap!) and for the 2003 Referenceware Excellence Award in the programming book category (I won? Cool!).

Since that point, I have worked to keep the book current with each release of the .NET platform, including a limited printing of a Special Edition, which introduced the technologies of .NET 3.0 (Windows Presentation Foundation, Windows Communication Foundation, and Windows Workflow Foundation) as well as offered previews of several forthcoming technologies, which we now know as LINQ.

The fourth edition of this text, which you hold in your hands, is a massive retelling of the previ-ous manuscript to account for all of the major changes that are found within .NET 3.5. Not only will you find numerous brand-new chapters, you will find many of the previous chapters have been expanded in great detail.

As with the earlier editions, this edition presents the C# programming language and .NET base class libraries using a friendly and approachable tone. I have never understood the need some technical authors have to spit out prose that reads more like a GRE vocabulary study guide than a readable book. As well, this new edition remains focused on providing you with the information you need to build software solutions today, rather than spending too much time examining esoteric details that few individuals will ever actually care about.