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

A strategy pattern implementation using FP/OOP


To focus on the programming model aspect, let us write a bubble sort routine to sort an array of the int, double, or float types. In a sort routine, we need to compare adjacent elements to decide whether one should swap the position of the elements. In computer science literature, this is called a comparator. Since we are using generic programming techniques, we can write a generic comparator interface to model the comparison action that would need to be performed while sorting is happening, and we will apply the strategy pattern to provide comparators based on types.

    interface IComparatorStrategy<T> 
    { int Execute(T a, T b); } 

Even though we can use a single generic implementation for comparing elements, in real life we might need concrete classes that are specific to the types. We will implement two concrete classes for the comparison of integers and doubles.

    class IntComparator : IComparatorStrategy<int> ...