Book Image

Improving your C# Skills

By : Ovais Mehboob Ahmed Khan, John Callaway, Clayton Hunt, Rod Stephens
Book Image

Improving your C# Skills

By: Ovais Mehboob Ahmed Khan, John Callaway, Clayton Hunt, Rod Stephens

Overview of this book

This Learning Path shows you how to create high performing applications and solve programming challenges using a wide range of C# features. You’ll begin by learning how to identify the bottlenecks in writing programs, highlight common performance pitfalls, and apply strategies to detect and resolve these issues early. You'll also study the importance of micro-services architecture for building fast applications and implementing resiliency and security in .NET Core. Then, you'll study the importance of defining and testing boundaries, abstracting away third-party code, and working with different types of test double, such as spies, mocks, and fakes. In addition to describing programming trade-offs, this Learning Path will also help you build a useful toolkit of techniques, including value caching, statistical analysis, and geometric algorithms. This Learning Path includes content from the following Packt products: • C# 7 and .NET Core 2.0 High Performance by Ovais Mehboob Ahmed Khan • Practical Test-Driven Development using C# 7 by John Callaway, Clayton Hunt • The Modern C# Challenge by Rod Stephens
Table of Contents (26 chapters)
Title Page
Copyright and Credits
About Packt
Contributors
Preface
8
What to Know Before Getting Started
17
Files and Directories
18
Advanced C# and .NET Features
Index

Typical issues resulting from legacy code


There is a reason we fear working on legacy code. But, what is it that we fear when working on legacy code? It's not the code itself; the code cannot harm us. Instead, what we fear is hearing that we have introduced a bug. The most dreaded word that a developer can hear. A bug means that we have failed and that we will have to work on the legacy code again.

Exploring the types of issues we might run into while working on legacy code, we find several. Firstly, because we don't know the code, a change to one part might cause unintended side effects in a different part of the application. Another issue is the code could be over-optimized or written by someone who was trying to be clever when they wrote it. Lastly, tight coupling can make updating the code difficult.

Unintended side effects

With all the changes that push an application towards the legacy realm, often the methods or functions in the application will be used in unexpected places, far away...