Gaurav Aroraa - Hands-On Design Patterns with C# and .NET Core

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To my mother, Late Smt. Santosh, and to the memory of my father, the late Sh. Ramkrishan, for
their sacrifices and for exemplifying the power of determination. To my youngest sister, the late
Baby Kanchan, for her love and always being my lucky charm.

My parents, Francis and Joyce, who tirelessly put their children first, with love, support, and kindness. To my brothers: Jack, for inspiring me to persevere through challenges, and Mike, for reminding me to stop and take the time to enjoy life.

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When designing good software, engineers naturally gravitate toward solutions that avoid duplication. We are naturally DRYDon't Repeat Yourselfoften without thinking about it! Developers naturally compartmentalize functionality, create reusable methods, and make helpful classes.

However, many software design patterns have been created over the years. These are useful, general, and reusable solutions to problems you'll see every day. There are more and more developers who are self-taught or who didn't go through a classical software engineer or computer science course at university, and everyone should enjoy the benefits of decades of development of these great design patterns.

Gaurav and Jeffrey have assembled the best and most common patterns and applied them to the open source world of .NET Core and C#. You'll start with OOP, classes, and objects and move your way on to inheritance, encapsulation, and polymorphism. They've covered design principles such as DRY, KISS, and SOLID (these will all make sense very soon!) and applied them to classic patterns that will help you make clear, crisp, and rock-solid (pun intended!) software.

This book is filled with real code that clearly illustrates how to apply all this knowledge to your .NET Core and C# software today. You'll learn how to adopt the Builder pattern, Decorator pattern, Factory pattern, Visitor pattern, and Strategy pattern, and so much more.

These techniques will then be applied to a simple app, then to a web application, and then to more complex problems involving concurrency and parallelism! You'll then apply patterns at a more macro level using solution patterns that will help you move your projects to the cloud in a scalable and maintainable way.

I hope you appreciate this book as much as I did. And I hope you enjoy working with .NET Core and have as much fun as we did making it!

Scott Hanselman

Partner Program ManagerMicrosoft

.NET and Open Source Community

This book is a blessing for every developer looking to raise their development skills to the next level, but more importantly, to build scalable, maintainable, and robust solutions. Most industry standards and best practices are covered, using straight-to-the-point examples.

Beyond development design patterns, the book also tackles underlying architecture principles and some key cloud aspects, such as security and scaling.

As a solution architect, I am involved day in day out in, designing end-to-end solutions, from the development aspects to the underlying infrastructure and security bits, and yet I am impressed by the quality contents and the broad scope of this book. It contains a very comprehensive list of patterns that everyone should take a look at when considering the development and deployment of new workloads.

This in-depth immersion into the Object-oriented programming (OOP) and .NET Core worlds is profitable to anyone interested in writing best-in-class applications.

Stephane Eyskens

Azure MVP

GauravAroraa has an M.Phil in computer science. He is a former Microsoft MVP, Alibaba Cloud MVP, certified as a Scrum trainer/coach, a lifetime member of