Real-World Implementation of C# Design Patterns

Overcome daily programming challenges using elements of reusable object-oriented software

Bruce M. Van Horn II

BIRMINGHAM—MUMBAI

Real-World Implementation of C# Design Patterns

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For my beautiful wife Karina, and my children Kitty and Phoebe, who helped me truly understand Ruth 1:16. In memory and gratitude to my mother and father, who paid for my first three computers, back when normal people didn’t own them. In memory of Dr. Charles Gettys for motivating me by telling me I would probably fail, and then teaching me everything he knew about computers. For Van Symons, who saw past my wheelchair and gambled on me when nobody else would, and who gave me a place and the opportunity to do the best work of my career. For my students at Southern Methodist University and Richland College, from whom I’ve learned as much as I’ve taught. For my work family at Clear Technologies/Visual Storage Intelligence. In memory of my student, Tom, who really could type ActionScript code with his feet. These are the people who inspire me and for whom I am deeply grateful. Above all, I am thankful to my Lord and Savior Jesus Christ who makes all things possible (Philippians 4:13), along with His Father who invented all the electrons and silicon, without which none of this computer stuff would exist (Genesis 1:14–19).

Foreword

I have known and worked with Bruce M. Van Horn II for the past 10 years. Bruce has been the lead software developer for Visual Storage Intelligence, an analytical software technology for analyzing infrastructure hardware and software to ensure the optimum use of on-premises and cloud resources is maximized. Bruce is a leader in creating and leveraging innovative software technologies to meet demanding customer needs in a fast-paced IT environment.

In this book, Bruce teaches you how to leverage software engineering techniques known as design patterns to solve real-world problems in an efficient and effective manner. Using patterns will help you solve problems effectively without reinventing the wheel. It will also keep your code healthy and stable.

Learning patterns are a must-have requirement in the career of any software engineer that we’ve hired at our start-ups. There is no question as to whether you should learn patterns; the question is really, where can you find a resource that teaches patterns in a way that is easy to understand and apply? There are many books on patterns in the marketplace but most have a very academic focus. This book is very different and somewhat unique. Instead of a dry treatment that reads like a doctoral thesis, Bruce presents you with the story of two sisters who form a tech start-up. Problems are encountered, requirements change, and at one point, so does the direction of the business. These are all normal and frequent occurrences, and the software that runs the company must be able to adapt. Most books cover development topics in a vacuum. All the designs are perfect, and the code always runs on the first try. That isn’t real life.

The story in this book follows a more realistic arc. The characters get into jams and use patterns to get out of them. Oftentimes, knowing when, where, and how to make use of these patterns can be critical to business success, and that’s what you’re going to learn in this book.

Bruce is not only a brilliant software engineer but also one of the best technology educators I have met in my 45-year career. He has the unique ability to not only understand the technology but also understand both the best places to make use of it, and also the places where specific technologies are not appropriate for the issues being analyzed.

Bruce shows you how to leverage the most important Gang of Four patterns in simple-to-understand examples, as well as how to use the patterns to solve problems in your daily work. Reading this book made software design patterns come to life and helped me understand how to leverage patterns in a real-world business context.

Van Symons

CTO Visual Storage Intelligence

Contributors

About the author

Bruce M. Van Horn II is an architect and lead developer for Clear Technology’s Visual Storage Intelligence SaaS product. He has over 30 years’ experience writing software and over 25 years’ experience teaching software development at a university level. He currently teaches full stack software development at Southern Methodist University’s code boot camp. He is a Certified ScrumMaster (CSM). Ten years ago, he was diagnosed with dermatomyositis and was told he would never walk, speak, or eat nachos again. Through faith and hard work, he beat the odds and today enjoys riding bicycles with his daughters, Katherine (Kitty) and Phoebe. He eats nachos regularly with Karina, the love of his life.

About the reviewers

Alexej Sommer is a professional .NET developer with expertise in a variety of technologies, including ASP.NET Core, WPF, UWP, Xamarin, and Azure.

He is also MCP/MCSD- and Azure-certified. He’s a winner of Microsoft’s Most Valuable Professional 2016–2019 in the Windows Development category. At present, he sometimes participates in conferences as a speaker.

Sarita Nag was born in India and she earned her master's degree in computer science from KIIT University, Bhubaneswar, Orissa.

Sarita began her career as Software Engineer from Thomson Reuters and since then, she worked on many multinational companies and is currently working at FISERV.

She is an experienced software engineer with passion for developing innovative programs that expedite the efficiency and effectiveness of organizational success. Well-versed in technology and writing code to create systems that are reliable and user-friendly.

She has 10+ years of experience in various phases of Software Development Life cycle (SDLC) and Agile methodologies such as Analysis, Design, Development, Testing, Deployment, and Maintenance in various domains like Tax and accounting, Financial, Communication Media, and Customer relationship.