Book Image

.NET Design Patterns

By : Praseed Pai, Shine Xavier
Book Image

.NET Design Patterns

By: Praseed Pai, Shine Xavier

Overview of this book

Knowing about design patterns enables developers to improve their code base, promoting code reuse and making their design more robust. This book focuses on the practical aspects of programming in .NET. You will learn about some of the relevant design patterns (and their application) that are most widely used. We start with classic object-oriented programming (OOP) techniques, evaluate parallel programming and concurrency models, enhance implementations by mixing OOP and functional programming, and finally to the reactive programming model where functional programming and OOP are used in synergy to write better code. Throughout this book, we’ll show you how to deal with architecture/design techniques, GoF patterns, relevant patterns from other catalogs, functional programming, and reactive programming techniques. After reading this book, you will be able to convincingly leverage these design patterns (factory pattern, builder pattern, prototype pattern, adapter pattern, facade pattern, decorator pattern, observer pattern and so on) for your programs. You will also be able to write fluid functional code in .NET that would leverage concurrency and parallelism!
Table of Contents (22 chapters)
.NET Design Patterns
Credits
Foreword
About the Authors
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface

Electronic spread sheets - A quintessential example


Electronic spreadsheets such as Excel software help one to input values in Cells, in a program-specific manner (for example-A7 , B6, and so on). They also allow you to embed computation as a value of a cell (such as =$A7*$B6 ) using formulas. Whenever a value is changed in A7 or B6, the resulting formula will be recomputed. Actually, the change is propagated to cells where there is reference to the cell which changed. This can be called a type of reactive computation. Let's see our Pythagorean triple generation in action on Excel:

In the preceding table, you can see that column F indicates (achieved with conditional formatting using icon sets) whether a, b, and c are Pythagorean triples or not.

The hidden columns D and F compute the values of (a2 + b2 ) and c2 independently, and column F just checks for an equality in order to display a potential match. All these are done, of course, using formulas, and the changes across cells are propagated...