Long ago (1995), four object-orientation specialists came out with a book called Design Patterns. In it, the four--whose book became so famous that they became known as the Gang of Four--forwarded a convincing argument that most programming jobs fell into a couple of dozen general categories, and that generic solutions to these programming problems--design patterns--could carry the day a lot of the time. The book remains part of the Holy Writ of object orientation, and indeed if you study it carefully you can save yourself from having to reinvent the wheel every time you set about writing software. Not long ago (2003), Microsoft came out with a new programming language called C#. It's object oriented, and does lots of nifty stuff with networks. Design Patterns in C# shows you how to implement the 23 "Gang of Four" design patterns in this new language. Steven Metsker's approach is mostly architectural, with lots of object relationship diagrams and relatively little code. He says right up front: "This book is for developers who know C# and want to improve their skills as designers." Among the most valuable parts of his coverage are his comparisons of similar patterns. These clarify, for example, when to use a Builder pattern, as opposed to a Factory or Abstract Factory. The approach helps you become a good C# architect. --David Wall
Topics covered: How to implement the 23 classic Gamma-Helm-Johnson-Vlissides design patterns in C#. Questions scattered throughout the text help you improve your C# skills while you read about pattern architecture.
Steven John Metsker explains how to use C# as an object-oriented language, using design patterns to create clean code while taking advantage of the extensive Microsoft(R) .NET Framework Class Libraries.
For all 23 classic "Gang of Four" design patterns, Metsker offers detailed code examples utilizing C# and the .NET Framework--as well as programming exercises crafted to help you rapidly build expertise. His exercises and explanations make extensive use of the Unified Modeling Language, helping you build your skills in this standard notation.
Design patterns covered include:
- Interfaces: Adapter, Facade, Composite, and Bridge
- Responsibility: Singleton, Observer, Mediator, Proxy, Chain of Responsibility, and Flyweight
- Construction: Builder, Factory Method, Abstract Factory, Prototype, and Memento
- Extensions: Decorator, Iterator, and Visitor
If you've already used design patterns in other languages, Design Patterns in C# will deepen your understanding, build your confidence, and help you apply them to any C# project. If you're a Microsoft programmer who's new to design patterns, this book will be an ideal practical introduction.
About the Author
STEVEN JOHN METSKER has written extensively on design patterns, object-oriented programming, and software methodologies. Steve is a software consultant with CapTech Ventures, and a frequent speaker at OOPSLA conferences. His work has appeared in journals including Java Report, JOOP, Distributed Object Computing, and Object Magazine. Steve's Addison Wesley books include Design Patterns Java Workbook and Building Parsers in Java.
Excerpt. © Reprinted by permission. All rights reserved.
Preface
It seems a long time ago (two years!) that I received the initial encouragement for this book from Paul Becker, an editor at the time with Addison-Wesley. I remain grateful to Paul for his help, and to his successor, John Neidhart, who took over as editor when Paul left. I am also grateful for the encouragement of John Vlissides, who is the Patterns Series editor and who has been a supporter of mine for all three of my books.
John Vlissides is also, of course, one of the four authors of Design Patterns. John and his co-authors--Erich Gamma, Ralph Johnson, and Richard Helm--produced the work that not only established a list of important patterns that every developer should know, but also set a standard for quality and clarity that I have aspired to attain in my own writing.
In addition to relying heavily on Design Patterns, I have benefited from the use of many other books; see Bibliography on 439. In particular, I have depended on The Unified Modeling Language User Guide Booch for its clear explanations of UML. For concise and accurate help on C# topics, I have consulted C# Essentials Albahari almost daily. I have also repeatedly drawn on the insights of C# and the .NET Platform Troelsen, and for realistic fireworks examples, I have consistently consulted The Chemistry of Fireworks Russell.
As the present book began to take shape, several excellent reviewers helped to guide its progress. I would like to thank Bill Wake for his early reviews. Bill never ceases to amaze me in his ability to catch the subtlest errors while simultaneously providing advice on overall direction, content, and style. I would also like to thank Steve Berczuk and Neil Harrison. In particular, they hit on the same key point that the book needed more introductory material for each pattern. Their comments drove me to rework the entire book. It is much stronger now because of their advice.
With the help of editors and reviewers, I was able to write this book; but, the text of a book is just the beginning. I would like to thank Nick Radhuber and the entire production staff for their hard work and dedication. Their work renders text into what is to this day its most usable form--a book!
Steve Metsker ( Steve.Metsker@acm.org)
