Mastering Visual Studio 2022 E-Book

Romain Ottonelli Dabadie

• Herausgeber: Packt Publishing
• Kategorie: Fachliteratur
• Sprache: Englisch

Seitenzahl: 312

Veröffentlichungsjahr: 2024

Beschreibung

Mastering Visual Studio, one of the fastest and most comprehensive integrated development environments (IDEs), is crucial for building efficient, scalable, and modern apps. Written by a seasoned technical expert in .NET with over a decade of experience, Mastering Visual Studio 2022 helps you leverage the full capabilities of this powerful IDE.
Packed with step-by-step guidance and self-assessment tools, this book adopts a practical approach to helping you advance your Visual Studio expertise. You’ll explore complex topics such as debugging, testing, extension development, and CI/CD, and gain practical insights to enhance your skills. The book covers advanced coding analysis and refactoring techniques that will help improve code quality and maintainability. You’ll also get to grips with Visual Studio’s capabilities for multi-platform development; integrating machine learning models; and cloud development with Azure, AWS, and Google Cloud. You’ll master Git workflows, conflict resolution, and DevOps practices with GitHub Actions and Azure DevOps, ensuring seamless team collaboration and efficient deployment pipelines.
By the end of this book, you’ll have become proficient in Visual Studio 2022, as well as being able to craft your own customized experience and confidently create robust, high-quality applications.

Leseprobe

Mastering Visual Studio 2022

Develop apps like a pro with advanced Visual Studio techniques using C# and .NET

Romain Ottonelli Dabadie

Mastering Visual Studio 2022

Copyright © 2024 Packt Publishing

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First published: December 2024

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To my wife, Cassandre, for being on my side for so many years and being a strong source of support during this journey. To my daughter and her smile, which brings the sun to each day of my life.

– Romain Ottonelli Dabadie

Foreword

As someone who frequently shares tips and insights about Visual Studio, I’m continually surprised by how many powerful features remain hidden from developers. From time-saving shortcuts to advanced tools, even experienced developers who’ve used Visual Studio for years often miss out on its full range of capabilities. For junior developers or those new to the tool, the sheer volume of features can feel overwhelming, leaving many unsure of where to start.

Visual Studio has also improved dramatically over the past few years, but staying updated with these advancements can feel like a full-time job. There’s no single place to learn everything it has to offer, so most developers pick up their knowledge in an ad-hoc, piecemeal fashion—from blogs, YouTube videos, social media, and other sources. This book is an invaluable resource, gathering scattered knowledge, tips, and hidden gems into a cohesive guide.

What makes this book stand out is its comprehensive, holistic approach to learning Visual Studio. It doesn’t just skim the surface but delves into both foundational tools and advanced capabilities that many developers might never discover on their own. The book covers essential topics such as mastering the debugger, code analysis, refactoring, and unit testing, as well as newer features like using .http files and Dev Tunnels for API work. It even includes in-depth content on starting with .NET Aspire and MAUI development in Visual Studio.

Beyond feature coverage, this book provides practical, actionable advice that developers can use immediately to enhance productivity. It includes real-world guidance on setting up effective Git workflows, integrating CI/CD pipelines with GitHub Actions and Azure DevOps, and even creating custom Visual Studio extensions and project templates to tailor the development environment to team-specific needs.

I’m thrilled to write this foreword. It’s evident that Romain has poured his expertise into creating a resource that will help developers unlock Visual Studio’s full potential. I’m excited to recommend this book to you and your team.

Dave Callan, Microsoft MVP

Contributors

About the author

Romain Ottonelli Dabadie, a seasoned Technical Expert in .NET, shapes the IT landscape in France and Canada. With over a decade of experience, he's a trusted professional, excelling in crafting robust solutions using Visual Studio. Romain's journey includes diverse roles, showcasing a commitment to excellence. Beyond his technical prowess, Romain actively engages on social media, sharing insights with the tech community. He stays abreast of Microsoft's latest developments, demonstrating a keen interest in their news and advancements. In the past decade, his proficiency in Visual Studio has driven solutions surpassing project expectations.

I would like to thank the people who have been close to me and supported me, especially my wife and my daughter.

About the reviewers

Nadir Riyani holds a Master’s in computer application and brings 15 years of experience in the IT industry to his role as an engineering manager. With deep expertise in Microsoft technologies, Splunk, DevOps automation, database systems, and cloud technologies, Nadir is a seasoned professional known for his technical acumen and leadership skills. He has published over 200 articles in public forums, sharing his knowledge and insights with the broader tech community. Nadir’s extensive experience and contributions make him a respected figure in the IT world.

Amr Saafan is a seasoned CTO and software consultant with over 20 years of experience in software development. He specializes in designing and developing applications for multiple industries such as telecommunication, healthcare, finance, and so on. As the founder of Nile Bits, he has successfully led projects for more than 200 clients across 15+ countries. Amr’s expertise includes system architecture, cloud services, software development, QA, and Agile coaching. He oversees technical teams, defines technology stacks, guides startups in product development, and is deeply involved in business development, software design, and talent acquisition.

Table of Contents

Preface

Part 1: Mastering Core Development Skills

1

Unit Testing and Test-Driven Development

Technical requirements

Introducing unit testing and TDD

The F.I.R.S.T principles of unit testing

TDD – unifying principles for software quality

AAA pattern – a structured approach to testing

Setting up unit testing in Visual Studio 2022

Creating a unit test project

Overview of the Test Explorer view

Creating a test with IntelliTest

IntelliTest execution and test generation

Saving, executing, and reviewing unit tests

Practicing TDD with a real-world example

Automating your tests with Live Unit Test

Configuring Live Unit Testing

Launching Live Unit Testing

Summary

2

Advanced Debugging Strategies

Technical requirements

Mastering Visual Studio Debugger

Entering debug mode

Advanced debug navigation

Understanding debugger tools

Fixing bugs on the fly

Advanced breakpoints and data inspections

Understanding the types of breakpoints

Organizing our breakpoints

Inspecting the data

Elevating debugging with auto-decomplication and External Sources

Auto-decompilation

External Sources

Concurrency debugging

Remote debugging

Summary

3

Advanced Code Analysis and Refactoring

Technical requirements

Understanding code analysis in Visual Studio

How Roslyn works

How does Visual Studio 2022 use Roslyn?

Utilizing static code analysis for quality assurance and security

Understanding how to use code analysis in Visual Studio

Adjusting the level of severity

Generating a .editorconfig file

Leveraging IntelliCode for code refactoring

Predicting code with whole-line autocompletion

Accessing GitHub documentation

Code metrics, maintainability, and security

Understanding the metrics

Using code metrics in Visual Studio 2022

Refactoring case studies

Handling common bad practice

Generating an interface

File-scoping our namespace

Summary

4

Performance Optimization and Profiling

Technical requirements

Introduction to performance optimization

Utilizing Visual Studio profiling tools

Analyzing .NET asynchronous events

Monitoring with .NET Counters

Tracking .NET Object Allocation

Viewing the event

Analyzing File I/O

Analyzing database performance

Instrumenting our .NET applications

Analyzing CPU Usage

Memory profiling and optimization

Using the Memory Usage tools

Exploring Memory Usage while debugging

Optimizing database interactions

Summary

Part 2: Advancing Development Horizons

5

Multi-Platform App UI Development

Technical requirements

An introduction to MAUI

The evolution of cross-platform development

What is MAUI?

The key features of MAUI

The architecture of MAUI

Exploring the tools for MAUI

Creating a simple MAUI app

XAML Live Preview

The Live Visual Tree

Debugging on devices

Enabling Developer Mode on our device

Networking device

Launching the debugging session

Migrate from Xamarin

Understanding the key differences

Using the .NET Upgrade Assistant

Summary

6

Advanced Web Development Tools

Technical requirements

Real-time web previews powered by Web Live Preview

Using API Explorer and Dev Tunnel with Visual Studio

Generating .http files with Endpoints Explorer

Configuring Dev Tunnel

Node.js integration with Visual Studio

Exploring JavaScript project templates

Managing npm packages

Debugging JavaScript applications

Summary

7

Machine Learning Integration

Technical requirements

Introduction to ML

Creating an ML model with ML.NET and the Model Builder UI

Deploying a model in an ASP.NET Core web API

Deploying a model in Azure Functions

Summary

8

Advanced Cloud Integration and Services

Technical requirements

Exploring .NET Aspire

Exploring Azure Functions development in Visual Studio

Exploring Google Cloud Tools for Visual Studio 2022

Exploring the AWS Toolkit

Summary

Part 3: Streamlining Collaborative Development with DevOps Practices

9

Handling Advanced Git Workflows

Technical requirements

Managing a repository through Visual Studio

Exploring the Manage Branches window

Looking at Checkout(-- detach)

Handling multiple repositories

Resolving conflicts through Visual Studio

Exploring interactive staging in Visual Studio

Summary

10

Continuous Integration with GitHub Actions

Technical requirements

Understanding GitHub Actions for CI/CD

Configuring workflows in GitHub Actions

Generating GitHub Actions file with Visual Studio

Summary

11

Collaborative Development with Azure DevOps

Technical requirements

Introduction to Azure DevOps

Setting up team projects

Implementing Agile development practices

Introducing Agile development

Managing Work Items through Visual Studio

Integrating Azure Pipelines for continuous integration

Summary

12

Visual Studio Container Tools for Docker

Technical requirements

Introduction to Docker and Visual Studio integration

Setting up Docker environments in Visual Studio

Creating a project with Docker support

Adding Docker support to an existing project

Dockerizing applications with Visual Studio

Deploying containerized applications

Deploying in Container Registry

Deploying as a service in Azure

Summary

Part 4: Mastering Core Development Skills

13

Writing Your Own Project Template

Technical requirements

Understanding project template structure

Building a basic project template

Customizing project templates for different workflows

Integrating template parameters and variables

Extending project templates with advanced features

Summary

14

Writing Your Own Visual Studio Extensions

Technical requirements

Understanding Visual Studio extension architecture

Building your first extension

Advanced extension features

Deploying and sharing your extensions

Summary

15

Creating and Publishing Powerful NuGet Packages for the Community

Technical requirements

Introduction to NuGet and package management

Creating your first NuGet package

Versioning and dependency management

Publishing and distribution

Advanced NuGet features

Target frameworks

Pre-release versions

Custom scripts

Summary

Index

Other Books You May Enjoy

Preface

Visual Studio is an essential tool for professional application development, particularly when working with C# and .NET. It provides developers with a comprehensive suite of features that simplify the process of creating, testing, and deploying robust applications. This book aims to guide developers in leveraging the full potential of Visual Studio’s advanced capabilities.

In this book, we will focus on four critical aspects of modern software development:

Core development skills, such as testing, optimization, debugging, and refactoring, which are crucial for writing clean and efficient codeAdvanced development techniques, including multi-platform app development, web tools, machine learning integration, and cloud services, enabling you to push your development capabilities furtherDevOps practices, which streamline collaborative development using Visual Studio’s built-in tools for advanced Git workflows, continuous integration with GitHub Actions, and Azure DevOps for effective team collaborationCustomization and enhancement, empowering you to tailor Visual Studio to your unique workflow by creating your own templates, extensions, and powerful NuGet packages

This book draws on my years of experience in software development, as well as insights from leading professionals in the field who have mastered Visual Studio’s most advanced features. As Visual Studio continues to evolve, developers will increasingly rely on its tools for efficient and scalable development. The key to success lies not just in writing code but in mastering the full development life cycle, from design to deployment, with the help of Visual Studio’s powerful features.

By mastering these techniques, you’ll be well-equipped to meet the challenges of modern application development, enhance your productivity, and deliver professional-grade applications with ease.

Who this book is for

This book is designed for developers, team leads, and IT professionals who want to elevate their expertise in Visual Studio and C#/.NET application development. The following groups will benefit the most from this content:

Professional developers: Developers looking to advance their knowledge of Visual Studio’s advanced features and improve their skills in areas such as testing, optimization, debugging, and DevOps integration. This book will help them build more efficient, scalable, and professional-grade applications.Development team leads: Team leaders seeking to streamline workflows, implement effective DevOps practices, and enhance collaboration within their teams using Visual Studio’s powerful tools. This book will help them manage multi-platform and cloud-based projects more efficiently.IT and DevOps professionals: Those responsible for managing development environments, automating deployment pipelines, or supporting development teams will gain valuable insights into advanced Git workflows, continuous integration, and containerization with Docker. This book provides practical guidance for optimizing Visual Studio for team collaboration and project success.

Whether you’re focused on coding, managing development teams, or handling DevOps tasks, this book offers the tools and knowledge needed to master professional application development with Visual Studio.

What this book covers

Chapter 1, Unit Testing and Test-Driven Development, introduces the importance of unit testing and TDD principles. It covers how to write effective unit tests using Visual Studio and integrate testing seamlessly into your development workflow.

Chapter 2, Advanced Debugging Strategies, explores debugging techniques beyond the basics. You’ll learn how to utilize Visual Studio’s advanced debugging tools to identify, isolate, and resolve complex issues in your code.

Chapter 3, Advanced Code Analysis and Refactoring, focuses on analyzing and refactoring code to improve quality and maintainability. This chapter covers tools and methods to identify code smells and enhance your code’s structure.

Chapter 4, Performance Optimization and Profiling, teaches you how to use Visual Studio’s profiling tools to analyze performance bottlenecks and optimize application speed, memory usage, and efficiency.

Chapter 5, Multi-Platform App UI Development, delves into building responsive, cross-platform applications. You’ll learn how to develop user interfaces that run smoothly on different devices and platforms using Visual Studio.

Chapter 6, Advanced Web Development Tools, introduces advanced features of Visual Studio to build modern web applications. This chapter covers tools and frameworks that enable scalable, high-performance web development.

Chapter 7, Machine Learning Integration, explores how to incorporate machine learning models into your applications. You’ll learn to leverage Visual Studio to develop intelligent applications powered by machine learning.

Chapter 8, Advanced Cloud Integration and Services, focuses on integrating cloud services into your applications. You’ll explore advanced cloud tools and services available through Visual Studio for scalable cloud-based applications.

Chapter 9, Handling Advanced Git Workflows, introduces advanced Git concepts and workflows. You’ll learn how to manage complex Git operations and collaborate effectively using Visual Studio’s integrated Git tools.

Chapter 10, Continuous Integration with GitHub Actions, covers setting up continuous integration pipelines using GitHub Actions. This chapter explains how to automate testing and deployment processes directly from Visual Studio.

Chapter 11, Collaborative Development with Azure DevOps, explores how to manage collaborative projects using Azure DevOps. You’ll learn how to integrate Azure DevOps with Visual Studio to streamline team collaboration and project management.

Chapter 12, Visual Studio Container Tools for Docker, teaches you how to use Visual Studio’s built-in container tools to develop, test, and deploy applications with Docker. This chapter covers containerization best practices and workflows.

Chapter 13, Writing Your Own Project Template, covers how to create custom project templates in Visual Studio to streamline development workflows. You’ll learn to tailor templates to meet your project’s specific needs.

Chapter 14, Writing Your Own Visual Studio Extensions, explains how to develop Visual Studio extensions to enhance your development environment. This chapter provides step-by-step instructions to build and publish your own extensions.

Chapter 15, Creating and Publishing Powerful NuGet Packages for the Community, focuses on creating reusable, shareable NuGet packages. You’ll learn how to package and publish your code to the community or enterprise to streamline development for other developers.

To get the most out of this book

You should have a basic understanding of the C# and .NET platforms. Some sections may reference cloud subscription tiers, but a subscription is not mandatory to follow along with most of this book.

Software/hardware covered in the book

Operating system requirements

Visual Studio

Windows

.NET

C#

Amazon Web Service (AWS)

Azure

Google Cloud Platform (GCP)

As Visual Studio evolves quickly, I recommend using the latest preview version of the IDE for the best experience and to experiment with the latest features.

If you are using the digital version of this book, we advise you to type the code yourself or access the code from the book’s GitHub repository (a link is available in the next section). Doing so will help you avoid any potential errors related to the copying and pasting of code.

Download the example code files

You can download the example code files for this book from GitHub at https://github.com/PacktPublishing/Mastering-Visual-Studio-2022. If there’s an update to the code, it will be updated in the GitHub repository.

We also have other code bundles from our rich catalog of books and videos available at https://github.com/PacktPublishing/. Check them out!

Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles. Here is an example: “Use the nuget push command or integrate with your CI/CD pipeline to automate the process.”

A block of code is set as follows:

<PropertyGroup>   <TargetFrameworks>net46;netstandard2.0</TargetFrameworks> </PropertyGroup>

Any command-line input or output is written as follows:

git add Car.cs

Bold: Indicates a new term, an important word, or words that you see on screen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “Right-click on the project in Solution Explorer.”

Tips or important notes

Appear like this.

Get in touch

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Part 1: Mastering Core Development Skills

In this first part, we explore the essential skills needed to elevate your software development practices to a professional level. By breaking down core development skills, including testing, optimization, debugging, and refactoring, each of these areas will sharpen your ability to write cleaner, more efficient code and tackle complex challenges with confidence, ultimately improving your overall development process, thanks to Visual Studio’s powerful assets and tools.

This part has the following chapters:

Chapter 1, Unit Testing and Test-Driven Development Chapter 2, Advanced Debugging Strategies Chapter 3, Advanced Code Analysis and Refactoring Chapter 4, Performance Optimization and Profiling

1

Unit Testing and Test-Driven Development

This chapter delves into the foundational concepts of unit testing and Test-Driven Development (TDD) within Visual Studio 2022. You will learn about the significance of writing tests before code and explore the integration of testing frameworks. Practical examples will guide you through creating effective unit tests, ensuring code reliability, and fostering a test-driven mindset.

We will embark on a journey to understand the essentials of unit testing and TDD. We’ll start by gaining an overview of these foundational concepts and exploring their significance in the software development life cycle.

Following this introduction, we will delve into the practical aspects of setting up unit testing within Visual Studio Code. This section will guide you through the initial steps of configuring your development environment, laying the groundwork for the integration of testing frameworks into your workflow.

Once the setup is complete, we will transition into creating our first test using IntelliTest, a feature of Visual Studio that automates the generation of unit tests. This hands-on experience will demonstrate how IntelliTest can streamline the testing process, making it more efficient and less time-consuming.

Next, we will apply what we’ve learned in a real-world example, practicing TDD from the ground up. This section will walk you through the process of writing tests before code, a core principle of TDD, and how it can lead to more robust and reliable software.

Finally, we will explore how to automate your testing process with Live Unit Testing, a feature that runs your unit tests in the background as you code. This section will show you how to enable and utilize Live Unit Testing to enhance your development workflow, ensuring that your code remains reliable and bug-free throughout the development process.

In this chapter, we’re going to cover the following main topics:

Introducing unit testing and TDDSetting up unit testing in Visual StudioCreating tests with IntelliTestPracticing TDD with a real-world exampleAutomating your tests with Live Unit Test

Technical requirements

While writing this chapter, I used the following version of Visual Studio:

Visual Studio Enterprise 2022 version 17.12.0Preview 1.0

The code files for this chapter can be found at https://github.com/PacktPublishing/Mastering-Visual-Studio-2022/tree/main/ch01

Introducing unit testing and TDD

Before delving into the usage of unit testing and the TDD approach through Visual Studio, let’s begin with a refresher on what they are and why it’s valuable to consider them in your project.

Unit testing is a focused software testing method that targets individual units or components within a software system. The primary aim of unit testing is to ensure that each software unit functions as intended, meeting specified requirements. Typically conducted by developers, unit testing takes place early in the development stage, preceding the integration and testing of the entire system.

Automated unit tests are executed whenever code undergoes modification, ensuring that new changes do not disrupt existing functionality. These tests are meticulously crafted to validate the smallest conceivable unit of code, such as a function or method, in isolation from the broader system. This approach empowers developers to swiftly identify and address issues in the initial phases of development, thereby enhancing overall software quality and reducing the time needed for subsequent testing phases.

The F.I.R.S.T principles of unit testing

By conscientiously embracing the Fast, Isolated/Independent, Repeatable, Self-Validating, Timely (F.I.R.S.T.) principles in unit testing, developers are guided in the meticulous crafting of effective tests. These principles serve as a compass, steering the testing process toward excellence by instilling key criteria that underpin the reliability and robustness of unit tests.

Let’s look at each of the factors of F.I.R.S.T. in more detail:

Fast: The speed of execution is a fundamental characteristic of effective unit tests. It is imperative that unit tests run swiftly, as developers frequently execute them throughout the development process. A fast test suite provides rapid feedback, allowing developers to promptly identify and rectify issues. This not only accelerates the development cycle but also cultivates a culture of responsiveness, where developers are encouraged to run tests frequently. The ability to obtain quick feedback enhances the early detection of potential problems, fostering a proactive approach to software quality.Isolated/independent: Independence is a cornerstone principle in unit testing. Each unit test should operate in isolation, devoid of dependencies on other tests. The order in which tests are executed or the success or failure of one test must not impact the results of another. This isolation ensures that developers can pinpoint and address issues in a focused manner, simplifying the debugging process. By adhering to the principle of independence, developers gain the advantage of precisely identifying the source of a problem, thereby expediting the resolution process.Repeatable: The repeatability of unit tests is paramount for maintaining the integrity of the testing process. A unit test should consistently produce the same result every time it is executed. This consistency ensures reliability in the test results, facilitating a dependable and predictable testing environment. If a test fails, developers should be able to reproduce the failure consistently, enabling them to investigate and resolve issues with confidence. Repeatability is a cornerstone for establishing trust in the testing suite and the overall software development process.Self-validating: Unit tests should possess self-contained criteria for success or failure, requiring no manual interpretation. A self-validating test ensures unambiguous results, reducing the potential for misinterpretation. Developers can quickly understand the state of the code based solely on the test results, streamlining the debugging and issue-resolution processes. The self-validating nature of unit tests contributes to the clarity and effectiveness of the testing suite, enabling developers to make informed decisions based on the unambiguous outcomes of each test.Timely: Timeliness in test writing is a critical factor in the effectiveness of unit testing. Ideally, tests should be authored before the corresponding code is implemented. This proactive approach ensures that tests serve as a living specification for the desired behavior, guiding the implementation process. Writing tests in a timely manner establishes a foundation for a well-defined and controlled development cycle. Timely testing also plays a pivotal role in identifying and addressing issues early in the development cycle, reducing the likelihood of defects propagating to later stages of the software development process. Embracing timely testing enhances the overall efficiency and reliability of the software development life cycle.

Now that we’ve established a foundational understanding of unit testing and its principles, let’s turn our attention to the broader context of TDD.

TDD – unifying principles for software quality

These F.I.R.S.T principles seamlessly pave the way to an overarching methodology known as TDD. TDD merges design, development, and testing into a unified framework, providing developers with a comprehensive approach to not only crafting simple and clean code but also ensuring thorough testing. The incremental development approach systematically tests all facets of business logic, making TDD the gold standard for creating high-quality software. It embodies the best coding and design practices throughout the entire process.

The main purpose of TDD is to achieve simpler and more reliable code. For that, TDD follows a simple and effective process, illustrated by the red-green-refactor cycle:

Figure 1.1 – The TDD cycle

Let’s understand this TDD cycle in more detail:

Red – writing a failing test:

In the first phase of TDD, known as the Red phase, developers embark on the journey by articulating their intent through the creation of a failing test. This test specifically targets a small unit of functionality that has not yet been implemented. It serves as a tangible expression of the desired behavior, essentially outlining the expectations for the code that is yet to be written. It is important to note that, at this stage, the test is expected to fail since the corresponding functionality is absent from the code base.

The primary purpose of the Red phase is to set a clear objective for the subsequent development process. By initially focusing on the expected outcome without any code in place, developers define a roadmap for the functionality they are about to implement. This intentional act of writing a test before writing the code not only establishes a specification for the upcoming functionality but also helps solidify the developer’s understanding of the problem at hand.

Green – writing the minimum amount of code to pass the test:

Following the Red phase, the development process proceeds to the Green phase. Here, the developer crafts the minimal amount of code necessary to make the previously written test pass successfully. The emphasis during this phase is on simplicity and efficiency. The goal is not to create an elaborate solution but to address the immediate requirement highlighted by the failing test.

By concentrating on the bare minimum code required for success, developers foster a culture of simplicity and avoid unnecessary complexities. This focused approach encourages the creation of code that meets the specific needs outlined by the test, laying the foundation for a solution that is both functional and concise. The success of the test in this phase signifies the achievement of the targeted functionality, validating the initial expectations set in the Red phase.

Refactor – refactoring the code:

With a passing test in place, the development process enters the Refactor phase. At this juncture, the developer takes a step back to review and enhance the code that has been implemented. The primary objectives during refactoring are to improve the maintainability, readability, and extensibility of the code without altering its functionality.

Refactoring is a critical aspect of TDD as it ensures that the code base remains clean and adaptable to future changes. Developers strive to eliminate redundancies, improve naming conventions, and apply design patterns where appropriate. This phase reinforces the commitment to producing not only functional but also well-crafted code. The successful completion of this phase sets the stage for a code base that is not only effective but also sustainable in the long run.

Repeat – iterative process:

TDD follows an iterative approach, and the Repeat phase encapsulates the cyclical nature of this development methodology. The entire Red-Green-Refactor cycle is repeated for each new piece of functionality that needs to be implemented. This iterative process ensures a systematic and gradual evolution of the code base, with each cycle contributing to the overall development of the software.

By repeating the cycle, developers continually refine and expand the application, responding to evolving requirements and ensuring that the code remains aligned with the project’s objectives. This iterative nature of TDD promotes adaptability and agility, making it a valuable methodology for projects with changing or evolving requirements.

This approach not only ensures the creation of functional software but also cultivates a mindset of continuous improvement and adaptability in the development process.

AAA pattern – a structured approach to testing

Building upon the principles of TDD and F.I.R.S.T, another key methodology in the realm of unit testing is the Arrange-Act-Assert (AAA) pattern. This pattern provides a uniform structure for organizing tests within a suite. The AAA pattern contributes significantly to the readability and maintainability of test suites, aligning seamlessly with the overarching goals of TDD.

The AAA pattern breaks down a test into three distinct sections:

Arrange: This section is about setting up the test environment.

In the Arrange section, the focus is on preparing the environment for the test. This involves setting up the objects to be tested, bringing the System under Test (SUT) to a specific state, and configuring any dependencies. Whether instantiating objects directly or preparing test doubles dependencies, the goal is to establish a controlled and consistent starting point for the test.

Act: This section is about performing the action on the SUT.

The Act section is where the actual interaction with the SUT takes place. This involves invoking a method or action on the SUT, passing any required dependencies, and capturing the output value, if applicable. The Act phase is crucial for simulating the real-world usage of the system and observing its behavior.

Assert: This section focuses on verifying the expected outcome.

In the Assert section, the test makes explicit claims about the expected outcome. This may include checking the return value, inspecting the final state of the SUT and its collaborators, or verifying the methods called on them. The Assert phase is the culmination of the test, ensuring that the behavior aligns with the anticipated results.

The AAA pattern’s structured approach provides clarity and consistency across all tests in a suite. By adhering to this pattern, developers can easily comprehend and navigate through tests, ultimately reducing the maintenance cost of the entire test suite. Whether starting with Arrange, Act, or Assert, the AAA pattern accommodates different testing styles while promoting a unified and systematic testing methodology.

Now that we’ve had a tour of unit testing and TDD, let’s dive in and see how to create a unit test project within Visual Studio.

Setting up unit testing in Visual Studio 2022

In this section, we will first create a unit test project within Visual Studio. Once that is done, we’ll go through an overview of the Test Explorer view and its main options. The Test Explorer view serves as a central hub for all testing activities within the IDE, offering a comprehensive overview of our test suite’s status and performance. It allows us to easily navigate through test results, identify failures, and access detailed information about each test case.

Creating a unit test project

Visual Studio and .NET support three testing frameworks:

MSTest: This is the default testing framework provided by Microsoft for .NET applications. It’s fully integrated into Visual Studio and offers features for writing and running tests within the IDE.NUnit: This is a popular open-source testing framework for .NET applications. It provides a flexible and extensible platform for writing and executing tests and is widely used in the .NET community.xUnit: This is another open-source testing framework for .NET applications. It follows a more modern and flexible approach compared to MSTest and NUnit and is gaining popularity among .NET developers.

First, you need to create a new project for your test set, in the solution containing the project we want to test. Right-click on your solution and select Add | New Project.... This will take you to the following screen:

Figure 1.2 – Adding a new test project

I filtered this view by the three top dropdowns to keep displaying the template projects for testing available by default in Visual Studio. You may notice that the last two templates on the list mention Playwright. Playwright is a library that enables end-to-end testing for modern web apps. With it, you can create unit tests to assess the functionality of your user interface.

Since xUnit is the most used framework in the industry, we will focus on it for our examples.

Another way to create your unit test project is by right-clicking directly on your class in your code base and selecting Create Unit Tests from the menu:

Figure 1.3 – Selecting Create Unit Tests from the menu

This action will open a menu that allows you to configure your unit test project:

Figure 1.4 – The Create Unit Tests window

By default, this allows you to create an MSTestv2 project, but you can install additional extensions to use other frameworks. If you already have a unit tests project created, you may add your test methods to it.

Regardless of how you create them, all the tests in this project can be managed in the Test Explorer view and we will explore it in the next section.

Overview of the Test Explorer view

Test Explorer serves as a powerful and centralized tool in Visual Studio 2022, facilitating the management and execution of unit tests. This feature-rich window allows developers to seamlessly view, organize, and run their unit tests within the Integrated Development Environment (IDE).

To access Test Explorer, there are two options:

You can navigate to the Test menu in Visual Studio or utilize the convenient keyboard shortcut accessed by pressing Ctrl + E, releasing them, and then pressing T.Since version 17.6, you can use the all-in-one search feature to quickly access all the features provided by Visual Studio. Simply open an all-in-one search using the Ctrl + Q shortcut, type Test Explorer, then press Enter, and you’ll be directed to the Test Explorer window.

Here’s a visualization of the Test Explorer window:

Figure 1.5 – The Test Explorer window

The Test Explorer console provides a clear and organized view of all available tests, making it easy for developers to navigate through their test suites. This interface offers advanced functionality for test management, such as the following:

Categorize and group tests: Utilize attributes and categories to group tests based on functional areas, features, or specific requirements. This helps in creating a logical hierarchy and makes it easier to focus on specific subsets of tests. By default, tests are grouped based on Project, followed by Namespace, and then Class. If you wish to modify the organization of your tests, simply click on the Group By button in Test Explorer and choose a new grouping criterion:

Figure 1.6 – Test Explorer – Group By

Here is the description of the groups you can choose from:

Duration: Groups tests by execution time: Fast, Medium, and SlowState: Groups tests by execution results: Failed Tests, Skipped Tests,