Modern Full-Stack Web Development with ASP.NET Core E-Book

Alexandre Malavasi

• Herausgeber: Packt Publishing
• Kategorie: Wissenschaft und neue Technologien
• Sprache: Englisch

Seitenzahl: 496

Veröffentlichungsjahr: 2025

Beschreibung

In the ASP.NET Core ecosystem, choosing the right JavaScript framework is key to addressing diverse project requirements. Witten by a four-time Microsoft MVP with 16 years of software development experience, this book is your comprehensive guide to mastering full-stack development, combining ASP.NET Core’s robust backend capabilities with the dynamic frontend power of Vue.js, Angular, and React.
This book uses ASP.NET Core to teach you best practices for integrating modern JavaScript frameworks, and creating responsive, high-performance applications that deliver seamless client–server interactions and scalable RESTful APIs. In addition to building expertise in ASP.NET Core’s core strengths, such as API security, architecture principles, and performance optimization, the chapters will help you develop the essential frontend skills needed for full-stack development. Sections on Blazor take a C#-based approach to creating interactive UIs, showcasing ASP.NET Core’s flexibility in handling both server and client-side needs.
By the end of this book, you will have a complete toolkit for designing, deploying, and maintaining complex full-stack applications, along with practical knowledge of both backend and frontend development.

Leseprobe

Modern Full-Stack Web Development with ASP.NET Core

A project-based guide to building web applications with ASP.NET Core 9 and JavaScript frameworks

Alexandre Malavasi

Modern Full-Stack Web Development with ASP.NET Core

Copyright © 2025 Packt Publishing

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First published: February 2025

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ISBN 978-1-78913-278-6

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To my mother, Marli, for her unwavering love and sacrifices that shaped me. To my daughter, Myla, for inspiring me with her boundless curiosity and joy. And to my wife, Paula, for being my steadfast partner and the heart of our shared journey.

—Alexandre Malavasi

Contributors

About the author

Alexandre Malavasi, CTO at MARELO and 4x Microsoft MVP, is a speaker at international conferences and the author of global books on .NET. With 16 years of software development experience, he has led complex projects across Brazil, Europe, and the United States. Alexandre excels in managing projects within the Microsoft stack. He holds multiple certifications and two postgraduate degrees in software engineering. His expertise and contributions to the field, coupled with his leadership in large-scale projects, have established him as a thought leader and an expert in his domain.

I would like to first and foremost thank my loving and supportive wife Paula and my daughter Myla for their endless encouragement throughout this journey. A special thanks also to my business partners, Joaquim and Jacque, at MARELO for their collaboration and unwavering support, which have been instrumental in making this project a reality.

About the reviewers

Rodrigo Lobenwein is a full-stack developer with a rich background in business management and sales, having transitioned to software development after over 15 years of experience in these fields. Since 2021, he has focused on building and optimizing applications using .NET and React, leveraging his business acumen to deliver efficient, user-focused software solutions. He uses his background to deeply understand users’ needs while maintaining a strategic view of the business, always prioritizing process improvement and client satisfaction. Passionate about technology and committed to continuous learning, he loves to understand the core of problems and find effective solutions, always eager to expand his knowledge and skill set.

Alex Tjahjana is a seasoned digital transformation leader with over 25 years of expertise in software development, cloud, AI transformation, and DevOps. He consistently delivers innovative, reliable, and efficient solutions across a range of industries. His leadership has driven high-impact initiatives, including New Zealand’s largest multi-cloud deployment and AI-powered system transformations. Alex also advises clients on digital transformation strategies to optimize their business outcomes. He is passionate about leading teams, staying at the forefront of technology, and mentoring IT talent. He holds multiple certifications, including Azure Expert Architect, AWS Architect Professional, Cybersecurity Expert, DevOps Engineer, Scrum Master, and ITIL.

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To join the Discord community for this book – where you can share feedback, ask questions to the author, and learn about new releases – follow the QR code below:

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Table of Contents

Preface

Part 1: Core Web Development with ASP.NET Core and Blazor

1

Introduction to ASP.NET Core

Technical requirements

Understanding ASP.NET Core – exploring the framework and its benefits

Key features and architectural benefits

Development experience and ecosystem

Real-world applications and scalability

Continuous innovation and community support

Understanding the main project templates available for ASP.NET Core

MVC

ASP.NET Core Web API

Razor Pages

A deep dive into Blazor Server and Blazor WebAssembly

Worker Service

Exploring the ASP.NET Core architecture and its features

Startup and middleware in ASP.NET Core

DI in ASP.NET Core

The history of ASP.NET Core

Summary

2

Setting Up and Building Basic Applications

Technical requirements

Building your first ASP.NET Core application

Creating a new project in Visual Studio

Exploring the project structure

Project structure overview

The Controllers folder

Views and Razor Pages folders

ViewBag, ViewData, and TempData

Developing a simple page

Adding a controller

Creating a view

Understanding MVC architecture

Understanding the concept of routing

Summary

3

Middleware and Dependency Injection

Technical requirements

Understanding and implementing middleware in ASP.NET Core

Configuring middleware

Creating custom middleware

Middleware ordering

Fundamentals of dependency injection in ASP.NET Core

Evolution with frameworks and languages

DI in modern development

The future of DI

How DI promotes loose coupling

Deep dive into service registration

Registering and configuring complex dependencies

Troubleshooting common issues in DI for ASP.NET Core

Issues related to service lifetimes

Resolving circular dependencies

Improper service registrations

DI best practices in ASP.NET Core

Prefer constructor injection

Avoid the service locator pattern

Be mindful of lifetimes

Use interfaces

Summary

4

Configuration and Security

Technical requirements

Importance of configuration and security in ASP.NET Core

Configuration in ASP.NET Core

Overview of configuration in ASP.NET Core

Understanding configuration providers

Implementing authentication and authorization in ASP.NET Core

How authorization works in ASP.NET Core

Securing data and SSL in ASP.NET Core

Summary

5

Introduction to Blazor

Technical requirements

What is Blazor?

Blazor’s unique approach of using C# for client-side web development

History of Blazor and its evolution

Significance of Blazor in the ASP.NET Core ecosystem

Understanding WebAssembly

Key features of Blazor

Component-based architecture

Data binding

Routing

Summary

Part 2: Advanced Integration and Application Development

6

Advanced Blazor Development

Technical requirements

Exploring Blazor components and lifecycle

Component parameters

Lifecycle methods

Enabling component communication

Advanced component features

Deep diving into event handling in Blazor

Standard event handling

Creating custom events

Managing event propagation and preventing default behavior

Handling multiple events

Debouncing and throttling events

State management in Blazor applications

Cascading values

Dependency injection

Local storage

State containers

Summary

7

Advanced Component Architecture in Blazor

Technical requirements

Exploring advanced component architecture

Dynamic components

Component composition

Advanced parameter binding

Routing and navigation in Blazor

Route constraints

Dynamic routing

Implementing JavaScript interoperability in Blazor

Calling JavaScript from Blazor

Calling Blazor methods from JavaScript

Handling parameters and return values

Using JavaScript libraries

Introducing new render modes in Blazor (.NET 9)

Introduction to render modes

Blazor WebAssembly (Wasm) and Blazor Server – a recap

InteractiveServer

InteractiveWebAssembly

InteractiveAuto

Combining render modes

Summary

8

RESTful Services with ASP.NET Core – Part 1

Technical requirements

Understanding RESTful services principles

Key principles of RESTful services

Creating basic REST APIs with ASP.NET Core

Setting up the project

Configuring the project

Creating a controller

Testing and running the API

Handling requests and responses

Working with query parameters

Working with headers

Working with body data

Handling different response types

API versioning and documentation basics

API versioning

Creating versioned controllers

Summary

9

RESTful Services with ASP.NET Core – Part 2

Technical requirements

Exploring advanced routing techniques

Attribute routing

Advanced attribute routing with regular expressions

Multi-tenant routing with subdomains

Custom route handlers for dynamic endpoints

Versioning with query parameters and headers

Performance optimization for APIs

Caching strategies

Response compression

Asynchronous programming

Database optimization techniques

Connection pooling

Summary

10

Introduction to JavaScript Frameworks

Technical requirements

Overview of Angular

Setting up your Angular environment

Creating your first Angular project

Creating a basic Angular component

Getting started with React

Setting up the environment for React

Creating a basic React application

Creating React components

Understanding the basics of Vue.js

Creating a basic Vue.js component

Summary

11

Exploring Vue.js and Comparing Frameworks

Technical requirements

Deep dive into Vue.js

Vue.js Reactivity System

Difference between the Options API and the Composition API

Understanding state management in Vue.js

Component-level state management

State management with the Composition API

Routing and navigation in Vue.js

Dynamic routing

Framework comparison and selection criteria

React analysis

Angular analysis

Vue.js analysis

Criteria for framework selection

Summary

12

Integrating Vue.js with ASP.NET Core

Technical requirements

Vue.js and ASP.NET core integration

Creating the domain model

Creating the controller

Configuring ASP.NET Core to serve the Vue.js application

Creating the Vue.js application

Creating the Vue components

Running the logistics application

Performance considerations in full-stack applications

Frontend performance enhancement with Vue 3

Backend performance optimization with ASP.NET Core web API

Summary

13

Integrating Angular with ASP.NET Core

Technical requirements

Setting up Angular with ASP.NET Core

Creating an ASP.NET Core Web API project

Building a sample application

Creating the domain model

Creating the backend services

Creating the controller

Creating the Angular application

Creating the services for HTTP requests

Creating the Angular components

Configuring routes

Running the demo application

Summary

14

Integrating React with ASP.NET Core

Technical requirements

Setting up React with ASP.NET Core

Creating an ASP.NET Core Web API project

Building an online polling and voting system

Creating the domain model

Creating the pool service and vote hub

Creating the controller

Creating the React application

Running the demo application

Summary

Part 3: Good Practices for Full-Stack Projects

15

Planning and Structuring Full-Stack Projects

Project planning and design principles

Defining the scope of the project

UI/UX considerations

Principles of good software design

Architectural considerations for full-stack projects

Monolithic versus microservices architectures

Three-tier architecture

RESTful versus GraphQL

State management and data flow

Team collaboration and Agile methodologies

Agile methodologies

Collaboration between frontend and backend teams

Using tools for team collaboration

Agile practices for team efficiency

Summary

16

Performance, Deployment, and Maintenance

Performance optimization techniques

Server-side optimizations

Caching strategies

Database performance optimization

Code efficiency and refactoring

Client-side optimization for Blazor applications

Monitoring and continuous optimization

Deployment strategies for web applications

Single-server deployment

CI/CD pipelines for automated deployment

Containerization with Docker

Blue-green deployment

Canary releases

Rolling deployments

Cloud-based deployment

Maintenance and monitoring of live applications

Application monitoring tools

Analyzing performance metrics

Incident management and alerts

Automated testing for ongoing quality assurance

Routine maintenance tasks

Data backup and disaster recovery

Monitoring feedback loops for continuous improvement

Scaling applications for high traffic

Vertical scaling (scaling up)

Horizontal scaling (scaling out)

Load balancing

Caching for high traffic

Autoscaling in cloud environments

Database scaling techniques

Summary

Index

Other Books You May Enjoy

Preface

Hello there! Full-stack web development combines the strengths of server-side technologies with modern JavaScript frameworks, creating dynamic, high-performance applications. ASP.NET Core, with its flexibility and scalability, is a leading framework for building enterprise-grade applications, and when paired with frameworks such as Angular, React, or Vue.js, it offers endless possibilities for crafting full-stack solutions.

This book is designed to help you navigate the complexities of full-stack development by bridging the gap between frontend and backend technologies. Throughout this journey, we will focus on three key pillars:

Mastering server-side development with ASP.NET CoreSeamlessly integrating JavaScript frameworks into your projectsImplementing performance, security, and best practices for full-stack applications

While many resources introduce these technologies individually, this book provides a project-based approach to full-stack development, emphasizing the integration of ASP.NET Core with leading JavaScript frameworks.

Drawing from my extensive experience in the industry, I will guide you through real-world examples and practical insights, equipping you with the tools to create scalable, robust web applications.

As full-stack development continues to evolve, mastering the integration of frontend and backend technologies will be a key skill. This book will empower you to excel in building modern, efficient web solutions using ASP.NET Core and the JavaScript frameworks that best fit your projects.

Who this book is for

This book is ideal for beginners in web development who are eager to learn how to build full-stack applications using ASP.NET Core and modern JavaScript frameworks such as Angular, React, and Vue.js. Whether you are just getting started with web technologies or have basic experience with either frontend or backend development, this book offers a structured and hands-on approach to mastering full-stack development from the ground up.

Three key groups will benefit from this book:

Aspiring full-stack developers: Individuals who are new to full-stack development and want to learn how to build complete web applications by combining ASP.NET Core for the server side and popular JavaScript frameworks for the client sideBeginner backend developers: Those with a basic understanding of backend development who want to expand their knowledge and learn how to create user-friendly, dynamic interfaces using Angular, React, or Vue.jsFrontend developers: Frontend developers who are familiar with HTML, CSS, and JavaScript and are now looking to gain experience in building scalable server-side applications using ASP.NET Core

With clear explanations, practical examples, and real-world projects, this book is a perfect starting point for anyone who wants to dive into full-stack development and build robust, scalable applications from scratch.

What this book covers

Chapter 1, Introduction to ASP.NET Core, covers the basics of ASP.NET Core, exploring its architecture, key features, and available project templates. By the end, you’ll understand its history and build a simple web application, preparing you for more advanced topics in the following chapters.

Chapter 2, Setting Up and Building Basic Applications, guides you through setting up your ASP.NET Core development environment and creating your first web application. You’ll learn the essentials of the Model-View-Controller (MVC) architecture, as well as routing and controllers, which are fundamental to building and navigating applications. By the end, you will have a functional ASP.NET Core app and a solid foundation for future development.

Chapter 3, Middleware and Dependency Injection, explores two core concepts of ASP.NET Core: middleware and dependency injection. You’ll learn how to implement middleware to customize the request pipeline and manage services efficiently using dependency injection. By the end, you’ll be equipped to build adaptable, maintainable applications with clean and scalable code.

Chapter 4, Configuration and Security, covers the essentials of configuring ASP.NET Core applications across different environments, ensuring flexibility and reliability. You’ll also dive into authentication and authorization, learning to secure your applications against unauthorized access. Additionally, you will explore secure data handling practices and implement SSL to protect data in transit. By the end, you’ll have the skills to build secure, adaptable applications that are ready for modern web challenges.

Chapter 5, Introduction to Blazor, explores Blazor, a framework that allows you to build interactive web UIs using C#. You’ll learn how to create a basic Blazor WebAssembly application and discover the differences between client-side and server-side Blazor. Additionally, you’ll dive into Blazor’s component architecture and data binding, equipping you to build dynamic, responsive web applications.

Chapter 6, Advanced Blazor Development, dives into advanced Blazor topics, including component architecture and lifecycle. You’ll also learn how to handle events in Blazor to create responsive UIs, and master state management techniques to ensure your applications maintain smooth and consistent functionality. By the end, you’ll be equipped to build more complex, high-performing Blazor applications.

Chapter 7, Advanced Component Architecture in Blazor, explores advanced Blazor component architecture. You’ll learn to create dynamic components, manage complex UIs, and handle advanced routing with parameters. You’ll also dive into JavaScript interoperability, allowing you to integrate JavaScript libraries with Blazor. Finally, you’ll discover the new render modes in Blazor (.NET 8), optimizing performance and user experience in your applications.

Chapter 8, RESTful Services with ASP.NET Core – Part 1, introduces the foundational concepts of RESTful services and guides you through building basic REST APIs using ASP.NET Core. You’ll learn the principles of REST, how to create and configure APIs, handle requests and responses, and implement versioning and documentation. By the end, you’ll have the skills to build well-structured, maintainable REST APIs.

Chapter 9, RESTful Services with ASP.NET Core – Part 2, delves into more advanced aspects of REST API development, focusing on complex routing techniques and performance optimization. You’ll learn how to create flexible API endpoints and apply strategies such as caching and asynchronous programming to improve API efficiency. By the end, you’ll have the skills to build scalable, high-performing APIs using ASP.NET Core.

Chapter 10, Introduction to JavaScript Frameworks, provides an introduction to the three most popular JavaScript frameworks: Angular, React, and Vue.js. You’ll learn the foundational principles of each framework, explore their key features, and understand their use cases. By the end, you’ll be equipped to start working with these frameworks and apply them to simple web projects.

Chapter 11, Exploring Vue.js and Comparing Frameworks, takes a deeper look at Vue.js, covering advanced features such as state management, routing, and navigation. You’ll gain practical skills for building more complex Vue.js applications while exploring how Vue.js compares to Angular and React. By the end, you’ll be well-equipped to build scalable Vue.js applications and choose the best JavaScript framework for your projects.

Chapter 12, Integrating Vue.js with ASP.NET Core, focuses on integrating Vue.js with ASP.NET Core to build full-stack applications. You’ll learn how to manage data flow between the frontend and backend, implement secure authentication and authorization, and optimize your application’s performance. By the end, you’ll be ready to create efficient, scalable full-stack applications using these two powerful technologies.

Chapter 13, Integrating Angular with ASP.NET Core, guides you through integrating Angular with ASP.NET Core to create scalable full-stack applications. You’ll learn how to set up both frameworks, implement secure API communication, and optimize performance. By the end, you’ll be equipped to build dynamic, high-performance applications using Angular for the frontend and ASP.NET Core for the backend.

Chapter 14, Integrating React with ASP.NET Core, walks you through integrating React with ASP.NET Core to build dynamic, scalable full-stack applications. You’ll learn how to configure both technologies, establish efficient data communication, and optimize performance for a seamless user experience. By the end, you’ll have the skills to create high-performing full-stack applications using React for the frontend and ASP.NET Core for the backend.

Chapter 15, Planning and Structuring Full-Stack Projects, focuses on planning and organizing full-stack web projects to ensure both frontend and backend components work seamlessly. You’ll learn how to set project objectives, design scalable architectures, and apply version control strategies. Additionally, we’ll cover Agile methodologies for team collaboration, ensuring efficient project management from planning to deployment.

Chapter 16, Performance, Deployment, and Maintenance, explores critical strategies for optimizing the performance of full-stack applications, from backend efficiency to frontend responsiveness. You’ll learn deployment techniques to ensure smooth launches and post-deployment monitoring and maintenance practices to keep applications running at peak performance. The chapter also covers scaling applications to handle high traffic, ensuring long-term stability and growth.

To get the most out of this book

To fully benefit from this book, basic knowledge of web development, including HTML, CSS, JavaScript, and C#, is helpful. Familiarity with setting up a development environment and using Git will also make it easier to follow along.

Software/hardware covered in the book

Operating system requirements

Visual Studio 2022

Windows, macOS, or Linux

Visual Studio Code

Node 21.x

.NET 9

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.

After reading this book, I encourage you to take on real-world projects, contribute to open source communities, or explore more advanced topics related to software architecture and advanced concepts of C# and ASP.NET Core. Applying the concepts from this book will solidify your knowledge of full-stack development and help you stay ahead in your career.

Download the example code files

You can download the example code files for this book from GitHub at https://github.com/PacktPublishing/Modern-Full-Stack-Web-Development-with-ASP.NET-Core. 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: “In this folder structure, the node_modules directory contains all the necessary dependencies and packages required by your application.”

A block of code is set as follows:

import React from 'react'; function MyComponent() {   return (     <div className="my-component">       <h2>This is my first React component!</h2>       <p>Congratulations for your first component.</p>     </div>   ); } export default MyComponent;

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

<h1>Hello, {{ title }}</h1>       <p>Congratulations! Your app is running. 🎉</p>       <br>       <p>         <app-my-component></app-my-component>       </p>

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

ng generate component my-component --standalone

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “If you open the application in your browser, you'll see the component's content being displayed alongside the message specified in the title property – that is, My first Angular component.”

Tips or important notes

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Part 1: Core Web Development with ASP.NET Core and Blazor

In this part, you will be introduced to the core concepts of ASP.NET Core and Blazor, two essential frameworks for modern full-stack development. You will explore the architecture and features of ASP.NET Core, set up your development environment, and build your first web application. Additionally, you will dive into Blazor, understanding how it enables building interactive web UIs using C#.

This part includes the following chapters:

Chapter 1, Introduction to ASP.NET CoreChapter 2, Setting up and Building Basic ApplicationsChapter 3, Middleware and Dependency InjectionChapter 4, Configuration and SecurityChapter 5, Introduction to Blazor

1

Introduction to ASP.NET Core

Welcome to Modern Full-Stack Web Development with ASP.NET Core, an essential guide designed to kickstart your journey into one of the most popular and robust web development frameworks available today. ASP.NET Core is a modern, open-source, cross-platform framework for building web-based, internet-connected applications.

In this chapter, we’ll delve into the core components of ASP.NET Core, providing you with a comprehensive understanding of its architecture, functionalities, and how to harness its capabilities for building efficient web applications.

By engaging with the upcoming lessons and activities, you’ll gain hands-on experience in setting up your development environment, creating a basic web application, and exploring the essential building blocks of ASP.NET Core, such as Model-View-Controller (MVC) patterns, dependency injection (DI), middleware, and more. You’ll learn not just the theory but also apply the concepts in practical tasks, enabling you to build and deploy a simple yet functional web application by the end of this chapter.

Understanding ASP.NET Core is invaluable for any web developer aiming to create robust, scalable, and maintainable web applications. By mastering the fundamentals outlined in this chapter, you’ll be equipped with the knowledge and skills to explore more advanced features and best practices in subsequent chapters.

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

Introduction to ASP.NET Core – understanding the framework and its advantagesUnderstanding the main project templates available for ASP.NET CoreExploring the ASP.NET Core architecture and its featuresHistory of ASP.NET Core

This structured approach will enable you to navigate this chapter efficiently and focus on sections that are most relevant to your learning path.

Technical requirements

Before diving into the hands-on exercises for ASP.NET Core in this book, it’s crucial to establish the technical foundation that’s required to follow the upcoming chapters effectively. This section outlines the necessary technologies and installations you’ll need to maximize your learning experience and engage with the practical exercises provided efficiently:

.NET 9 framework: At the core of your development environment should be the .NET 9 framework. This latest version is essential for leveraging the new and improved features offered in ASP.NET Core. It provides a comprehensive and consistent programming model that’s crucial for building high-performance web applications. Ensure that you have .NET 9 installed on your system so that you can work through the examples and projects in this book seamlessly.ASP.NET Core (latest version): Alongside .NET 9, having the latest version of ASP.NET Core installed is imperative. This version is specifically designed to integrate with .NET 9, offering a powerful and efficient platform for web development. It’s the framework you’ll be interacting with throughout this book, so having it updated will ensure you have access to the latest tools and features.Development environment: For an optimal development experience, this book recommends using either Visual Studio or Visual Studio Code, depending on your preference:Visual Studio (latest version): Known for its comprehensive suite of development tools, Visual Studio is an excellent choice for ASP.NET Core development. It provides an integrated environment where you can write, debug, and deploy your applications efficiently. Ensure you have the latest version installed to benefit from the integrated support for .NET 9 and ASP.NET Core.Visual Studio Code (latest version): If you prefer a lighter yet powerful editor, Visual Studio Code is your go-to option. It supports a wide range of programming languages and frameworks, including C# and .NET, making it suitable for ASP.NET Core development. With its robust ecosystem of extensions, you can tailor the editor to your specific needs, enhancing your productivity and development experience.

By preparing your environment with these technical requirements, you’ll be well-equipped to tackle the ASP.NET Core projects and examples presented in this book, ensuring a smooth and effective learning journey.

Understanding ASP.NET Core – exploring the framework and its benefits

Before we start our journey into ASP.NET Core, you must understand the details of the path that you’ll be walking in this book.

ASP.NET Core stands as a groundbreaking development framework in the market for web development, offering a versatile and high-performance framework that caters to modern application needs. It has provided constant updates year after year for the last two decades. This section delves into the nature of ASP.NET Core, elucidating its core components, architectural advantages, and the benefits it brings to the development table.

ASP.NET Core is an open source, cross-platform framework for building modern, cloud-enabled, internet-connected applications. At its heart, it’s a redesign of classic ASP.NET, but with a modular, more efficient, and cross-platform runtime. This modern framework allows developers to build applications that can run on Windows, Linux, and macOS, thereby broadening the potential user base and deployment environments.

The framework’s inception was driven by the need to create a more modern web development platform that could address the evolving challenges and leverage the latest computing environments. ASP.NET Core’s architecture is lean and composable, providing developers with the flexibility to include only the necessary components in their applications. This optimizes performance and reduces resource consumption by helping them choose the correct and appropriate project templates.

Key features and architectural benefits

ASP.NET Core distinguishes itself in the web development domain with its exceptional cross-platform support, enabling developers to design and deploy applications across various operating systems, such as Windows, Linux, and macOS, without substantial code alterations. This flexibility not only expands the applications’ reach across diverse environments but also aligns with the modern trend toward platform-agnostic development, ensuring applications can cater to a wider audience, irrespective of their platform preferences.

The performance metrics of ASP.NET Core are equally impressive, showcasing significant enhancements over its forerunners. Its ability to deliver quick response times and minimize latency is crucial for applications that are expected to handle high loads efficiently. This performance edge is attributed to the framework’s optimized, lightweight architecture, which streamlines processes and reduces unnecessary overhead, ensuring applications remain agile and responsive under various operational conditions.

Modularity is another cornerstone of ASP.NET Core’s architecture, offering developers the flexibility to incorporate only the essential components needed for their applications. This not only reduces the overall size but also optimizes performance. Such modularity is invaluable for maintenance and updates, allowing for individual component enhancements without the need for broad, systemic revisions, thus keeping applications up to date and secure with minimal disruption.

Security is outstanding in ASP.NET Core, which fortifies applications with robust, built-in features safeguarding against prevalent web threats. Developers benefit from integrated support for critical security measures such as data protection, authentication, authorization, and cross-origin resource sharing (CORS) defenses, enabling them to build secure, reliable applications by default.

Integrating MVC and a Web API into a cohesive framework demonstrates ASP.NET Core’s streamlined and unified approach to web application and service development. This integration simplifies the development workflow, reducing the learning curve and fostering a more intuitive environment for developers, particularly those new to the platform.

Expanding its horizon, ASP.NET Core embraces modern web development trends with Blazor, a groundbreaking framework that allows developers to build interactive web user interfaces using C# instead of JavaScript. This innovative approach provides a seamless development experience, enabling the use of a single language across both client-side and server-side code, thus streamlining the development process and enhancing productivity.

Moreover, ASP.NET Core’s ability to integrate seamlessly with various JavaScript frameworks amplifies its versatility. This interoperability is crucial for developers leveraging the unique strengths of JavaScript frameworks such as Angular, React, and Vue.js alongside ASP.NET Core, facilitating the creation of rich, interactive, and highly responsive user experiences. The synergy between ASP.NET Core and these JavaScript ecosystems enables a more comprehensive development strategy that accommodates a wide array of project requirements and enhances the overall capability to deliver sophisticated, modern web applications.

Development experience and ecosystem

ASP.NET Core offers a superior development experience with its integration into the .NET ecosystem, providing access to a vast array of libraries and tools. Developers can leverage the powerful features of Visual Studio, Visual Studio Code, or any other editor of their choice and benefit from features such as IntelliSense, debugging, and unit testing.

The community and ecosystem around ASP.NET Core are vibrant and continuously evolving. Developers have access to a plethora of resources, including documentation, tutorials, forums, and third-party libraries, which facilitate the development process and encourage innovation.

Real-world applications and scalability

ASP.NET Core is designed to handle the demands of modern web applications, from small-scale projects to large, enterprise-level solutions. Its scalability is one of its strongest suits, enabling applications to grow in terms of users and functionality with minimal changes having to be made to the core architecture.

Companies and developers adopt ASP.NET Core for various applications, including web applications, mobile backends, IoT applications, and microservices. The framework’s versatility and performance make it suitable for a wide range of industries, including finance, healthcare, education, and e-commerce.

Continuous innovation and community support

The future of ASP.NET Core is promising, with continuous enhancements and updates being rolled out by Microsoft and the community. The framework is open source, which encourages community contributions and feedback, driving its evolution and ensuring it remains at the forefront of web development technologies.

In conclusion, ASP.NET Core is a powerful, modern framework that’s designed to meet the challenges of today’s web development landscape. Its benefits, including cross-platform support, performance, modularity, security, and scalability, make it an excellent choice for developers looking to build robust, maintainable, and efficient web applications.

Having explored the numerous advantages of utilizing ASP.NET, let’s progress to the subsequent section, where we’ll delve into the various project templates available for ASP.NET Core.

Understanding the main project templates available for ASP.NET Core

ASP.NET Core’s versatility is encapsulated in its range of project templates, each designed to cater to different web development needs. These templates not only offer a jumpstart for your projects but also integrate best practices, guiding you toward a structured and efficient development process. In this section, we’ll delve deeper into each primary template, offering a richer perspective to aid you in selecting the most fitting template for your specific project requirements.

MVC

The MVC template in ASP.NET Core serves as a robust foundation for building web applications that are scalable, maintainable, and testable. This in-depth exploration will unpack the MVC architecture, elucidating how each component operates within the framework and how this architecture facilitates a clean separation of concerns – a principle that’s vital for complex application development.

The MVC pattern is a well-established design paradigm in web application development that’s not only used by the .NET platform but by other technologies as well. ASP.NET Core’s MVC template forces the implementation of a clear pattern for web development that helps teams build complex applications while retaining simplicity and consistency in terms of software architecture. Understanding the roles and responsibilities of each component in this architectural pattern is crucial for leveraging its full potential:

Model: In MVC, the Model represents the application’s domain. It encapsulates the data and the business rules that govern access to and modifications of this data. In ASP.NET Core, models are typically implemented as classes with properties and methods. They can include data validation rules to enforce business logic, ensuring data integrity and consistency. Models aren’t just data structures; they embody the business logic of the application, making decisions and performing calculations based on the rules defined within them.View: The View is responsible for rendering the user interface in an MVC application. It displays data from the model to the user and sends user commands to the controller. In ASP.NET Core, views are often created using the Razor view engine, which allows developers to write HTML with embedded C# code. Razor views are dynamic and can react to the model data they receive, enabling the creation of interactive and data-driven user interfaces. This separation of UI rendering from business logic and input handling makes the views manageable and modular.Controller: A Controller is a coordinator in the MVC pattern. Controllers handle user input, work with the model to perform necessary actions or calculations, and determine which view should be rendered. In ASP.NET Core, controllers are C# classes that can contain multiple actions. These actions are methods that respond to different HTTP requests, invoking changes in the model and selecting views for response. Therefore, controllers act as an intermediary, translating user inputs into actions on the model and selecting views based on the outcomes of those actions.

The MVC template is particularly advantageous for developers looking to build applications with a clear separation of concerns, thereby facilitating easier testing, maintenance, and scaling. It comes pre-configured with essential features such as routing, authentication, and authorization, allowing you to focus on developing unique application features rather than boilerplate code. This project template has thefollowing benefits:

Separation of concerns: By dividing the application into three interconnected components, MVC naturally promotes a clean separation of concerns. This separation enhances the maintainability of the application as developers can work on models, views, or controllers independently without significant overlap in functionality.Testability: The clear delineation of responsibilities in the MVC pattern facilitates more straightforward testing. Models can be tested independently of user interfaces, controllers can be tested for correct routing and response, and views can be verified to render correctly given a model. ASP.NET Core further supports this testability with features such as DI, which can be used to inject mock implementations for testing.Modularity and flexibility: The MVC template’s compartmentalized structure allows for modular development and flexibility. Developers can iterate on the design, presentation, and business logic layers separately, adapting to new requirements or design changes with minimal impact on the overall code base.A rich ecosystem and community support: Given its popularity, MVC benefits from extensive community support, a wealth of documentation, tutorials, and a plethora of libraries that can be leveraged to add functionality to your application. ASP.NET Core’s MVC framework is no exception, with strong support from Microsoft and a vibrant community, ensuring developers have access to a wealth of resources and best practices.

The MVC template in ASP.NET Core is a powerful choice for developers looking to build web applications with a proven architecture that promotes clean coding practices, testability, and separation of concerns. Its structure is conducive to developing applications that aren’t only robust and scalable but also adaptable to evolving business requirements. By understanding and utilizing the MVC architecture to its full potential, developers can create dynamic, efficient, and maintainable web applications that stand the test of time. In the next few chapters of this book, you’ll have the opportunity to experience how to create applications using the MVC architecture while following a hands-on approach.

ASP.NET Core Web API

The API project template in ASP.NET Core is meticulously designed to streamline the creation of RESTful web services. This template is a boon for developers focusing on the backend services that power web and mobile applications, IoT devices, and more. Here, we’ll delve deeper into the components and features that make the API project template a go-to choice for building high-performance and scalable APIs. The following points clarify the main features of the ASP.NET Core Web API project template:

Foundation for RESTful services: The API project template lays the groundwork for adhering to REST principles, which emphasize stateless communication, resource identification through URIs, and the use of standard HTTP methods (GET, POST, PUT, and DELETE). This adherence simplifies the design of your API and aligns it with web standards, making it intuitive and straightforward to consume.Controller-based architecture: At the heart of the API template is the controller-based architecture. Controllers in ASP.NET Core serve as the entry point for handling HTTP requests and responding with data or status codes. Each controller is typically associated with a specific resource or a related group of resources, encapsulating the logic required to process incoming requests and generate responses.Routing and URL mapping: The API template configures routing to ensure that HTTP requests are directed to the appropriate controllers and actions. ASP.NET Core’s routing engine is capable of handling complex URL patterns and can be customized to fit the needs of your API, enabling you to define clear and descriptive routes that reflect your API’s resource hierarchy.Content negotiation and serialization: ASP.NET Core’s built-in support for content negotiation allows your API to serve data in various formats (such as JSON or XML) based on the client’s preferences or request headers. The framework automatically handles the serialization and deserialization of data, ensuring that your API can communicate effectively with different clients and systems.Model binding and validation: The API project template leverages ASP.NET Core’s model binding and validation features to streamline data processing. Model binding automatically maps data from HTTP requests to action method parameters, while applying validation attributes to your models helps ensure that incoming data meets your business rules before your application processes it.Error handling: Robust error handling is crucial for maintaining a reliable API. The API project template includes basic error handling mechanisms that you can extend to create a comprehensive error response strategy. This ensures that your API can gracefully handle and respond to various error conditions, providing meaningful feedback to the client.Testability: Just like other ASP.NET Core applications, APIs built using the API project template are highly testable. The framework’s support for DI, combined with the separation of concerns inherent in the controller-based architecture, allows you to write unit and integration tests that cover your business logic, routing, and response generation.Swagger integration: Developers often enhance APIs built with this template by integrating Swagger (OpenAPI), which provides interactive documentation, client SDK generation, and API discoverability. Although not included in the template by default, adding Swagger support is straightforward and significantly improves the developer experience when you’re working with your API.

By leveraging the API project template in ASP.NET Core, developers can create well-structured, performant, and scalable web services. This template not only provides the scaffolding necessary for RESTful API development but also ensures that the APIs are maintainable, testable, and compliant with industry standards, laying a solid foundation for any application’s backend services.

Razor Pages

Razor Pages, introduced in ASP.NET Core as an alternative to the MVC template, offers a streamlined approach to building web applications, emphasizing page-focused scenarios. This framework simplifies web development by integrating the server-side logic directly within the page markup, offering a more intuitive and productive way to construct dynamic web content. Let’s embark on a detailed exploration of Razor Pages, highlighting its architecture, advantages, and how it differentiates itself within the ASP.NET Core suite:

Page-based programming model: Razor Pages centers around a page-based programming model that’s a departure from the controller and view-based MVC model. Each Razor Page is a self-contained unit consisting of a .cshtml file (which combines HTML markup with Razor syntax) and a code-behind file. This structure allows developers to encapsulate the page’s UI and business logic cohesively, promoting a high degree of modularity and maintainability.Code-behind model: The code-behind file in Razor Pages, typically a .cshtml.cs file, contains the server-side logic to handle user actions, data access, and other server-side operations. This separation keeps the markup clean and focused on presentation while maintaining a close association with the page’s logic. Developers can handle events, such as form submissions, directly within the page model, streamlining the development process.Razor syntax: Razor syntax is a powerful feature within Razor Pages that allows developers to embed C# code directly into their HTML markup. This syntax is intuitive and designed to work seamlessly with HTML, providing a robust way to dynamically generate content, control page flow, and interact with data. Razor’s syntax simplifies many common tasks, such as iterating over data collections, conditionally rendering content, and handling form inputs.Strongly typed data models: Razor Pages supports strongly typed data models, enabling developers to work with well-defined C# classes within their pages. This strong typing enhances code clarity, compile-time checks, and IntelliSense support in IDEs, reducing errors and improving developer productivity.Tag Helpers: Razor Pages leverages Tag Helpers to enable server-side code to participate in creating and rendering HTML elements in Razor files. Tag Helpers are a more readable and HTML-friendly way to define server-side logic compared to traditional MVC helpers. They can be used to easily bind form elements to data models, generate links, create forms, and more, all while maintaining a clear separation between HTML and C#.Routing and URL generation: Razor Pages introduces a simplified routing system that’s based on the file structure of the Pages folder. By default, the URL of a Razor Page corresponds to its location within the Pages directory. This convention-based routing reduces the complexity of defining routes and makes URL generation more intuitive.Built-in security features: Razor Pages come with built-in security features, such as request verification and cross-site scripting (XSS) protection, that safeguard the application against common web vulnerabilities. The framework enforces best practices such as automatically encoding output and validating request tokens to prevent CSRF attacks.Extensibility and customization: While Razor Pages provides a streamlined development experience out of the box, it also offers extensive options for customization and extensibility. Developers can create custom Tag Helpers, filters, and middleware to enhance functionality or integrate third-party libraries to extend the capabilities of their Razor Pages applications.

In conclusion, Razor Pages in ASP.NET Core presents a highly productive, page-focused framework for building web applications. Its integration of a UI and business logic within individual pages, support for Razor syntax and Tag Helpers, and a simplified routing model make it an attractive choice for developers seeking an alternative to the traditional MVC approach. Razor Pages strikes a balance between simplicity and power, offering a compelling model for constructing interactive, data-driven web applications.

A deep dive into Blazor Server and Blazor WebAssembly

Blazor is a groundbreaking project type in ASP.NET Core that fundamentally changes how interactive web applications can be built using the .NET ecosystem. With the introduction of .NET 9, Blazor has matured even further, offering new features and enhancements that bolster its performance, ease of development, and functionality. This deep dive explores both Blazor Server and Blazor WebAssembly, elucidating their architectures, key features, and the enhancements brought by .NET 9.

Blazor Server

Blazor Server allows you to build interactive web applications where the application logic and state management are handled on the server side. User interactions are managed through a SignalR connection, providing a robust, real-time communication channel between the client and server. The following points illuminate the key features of the Blazor Server project type and the advancements introduced in .NET 9:

SignalR-based state management: In Blazor Server, the client’s UI state is maintained in the server’s memory. When a user interacts with the UI, the event is sent to the server over a SignalR connection and processed, after which the required UI updates are sent back to the browser. This architecture minimizes the amount of data that’s transferred over the network and leverages the server’s capabilities for heavy lifting..NET 9 enhancements: With the advent of .NET 9, Blazor Server has seen improvements in performance and development experience. Enhancements in SignalR and rendering efficiencies reduce latency and improve the responsiveness of Blazor Server applications. Furthermore, improved hot reload capabilities in .NET 9 enhanced the developer experience, making UI adjustments and debugging more intuitive and faster.

Blazor WebAssembly

Blazor WebAssembly is the client-side counterpart of Blazor that enables running C# code directly in the browser using a WebAssembly-based .NET runtime. This model is akin to JavaScript frameworks but leverages the full power of .NET. The following points illuminate the key features of the Blazor WebAssembly project type and the advancements introduced in .NET 9:

WebAssembly runtime: The Blazor WebAssembly model downloads the .NET runtime, your application, and its dependencies to the browser, executing the application directly in the browser’s sandbox. This allows for rich interactive experiences without server roundtrips, something that’s ideal for offline-capable applications, complex client-side computations, and reduced server load..NET 9 enhancements: Blazor WebAssembly with .NET 9 introduces performance optimizations, smaller download sizes, and faster startup times. The runtime and tooling improvements in .NET 9 have made Blazor WebAssembly applications more efficient and quicker to load, enhancing the user experience, especially in resource-constrained environments.

Common features and improvements – Blazor Server and Blazor WebAssembly

The following are some common features and improvements that can be found in both Blazor Server and Blazor WebAssembly:

Component model: Both Blazor Server and Blazor WebAssembly utilize a component-based architecture that promotes reusability and maintainability. Components are the building blocks of Blazor applications and encapsulate markup, logic, and styling. They can be nested, reused, and shared between projects, fostering a modular development approach.JavaScript interoperability: Blazor provides extensive interoperability with JavaScript, allowing developers to leverage existing JavaScript libraries and frameworks. This interoperability is crucial for accessing browser APIs not exposed through Blazor and for integrating with third-party JavaScript-based UI libraries..NET 9-specific features: .NET 9 introduces more granular control over component rendering, improved error handling, and enhanced component life cycle methods. These features provide developers with more tools to optimize their applications and improve user experience.Mobile Blazor Bindings: With .NET 9, developers can experiment with Mobile Blazor Bindings, an exciting feature that allows Blazor components to be used to build native mobile applications using web technologies, extending the reach of Blazor beyond web browsers.PWA support: Blazor WebAssembly supports building progressive web applications (PWAs) out of the box. This feature enables applications to be installed on a user’s device, work offline, and leverage native device features, bridging the gap between web and native applications.

In summary, Blazor in .NET 9 continues to evolve, offering a compelling model for building web applications using C#. Whether you choose Blazor Server for its real-time capabilities and server-side processing or Blazor WebAssembly for its client-side execution and offline support, Blazor provides a robust platform for building modern web applications. The ongoing enhancements in .NET 9 further cement Blazor’s position as a versatile, performant, and developer-friendly framework in the .NET ecosystem.

Worker Service

The Worker Service template in ASP.NET Core is a versatile template that’s designed to help developers create background services for a variety of applications. These services can run in the background, executing tasks independently of user interfaces or web requests. This exhaustive overview delves into the architecture, key features, and practical applications of Worker Service templates, providing insights into how they can be utilized effectively in your .NET applications. The following points elucidate the main aspects of the Worker Service project type:

Core architecture: At its heart, a Worker Service in ASP.NET Core is a long-running console application that leverages the generic host (HostBuilder), which is also used in ASP.NET Core web applications. This shared foundation allows for the use of familiar features such as DI, logging, and configuration systems, making it easier for developers to transition between web and worker services.Background task execution: The Worker Service template is ideal for executing background tasks such as processing queues, polling databases, or performing timely operations. The template provides a base class, BackgroundService, from which you can derive to implement your long-running tasks. This class offers methods such as ExecuteAsync, which you can override to define the logic of your background tasks.Integration with hosted services: A Worker Service template can be registered as a hosted service within the .NET Core generic host. Each hosted service can run in parallel and independently, starting and stopping together with the application. This model provides a clean abstraction for implementing different background tasks that need to run throughout the life of the application.DI and configuration: Utilizing the built-in DI in ASP.NET Core, Worker Service can easily access configured services and settings, enhancing its modularity and testability. Configuration values can be read from various sources, such as appsettings.json, environment variables, or command-line arguments, allowing for flexible deployment and runtime behavior.Logging: ASP.NET Core’s logging infrastructure is fully supported in Worker Service, enabling you to integrate robust logging mechanisms that can log to various outputs, such as the console, files, or external data stores. This is crucial for monitoring the health and performance of your background services.Health checks: Worker Service can implement health checks, providing insights into the health and performance of the application. This feature is especially important for services running in production as it allows for proactive monitoring and maintenance.Windows services and Linux daemons: One of the significant advantages of Worker Service is its ability to be hosted as Windows services or Linux daemons. This means that your Worker Service template can run automatically in the background as a system service, without requiring a user to log in.Containerization: Worker Service is well-suited for containerization with Docker. Running a Worker Service template in a container allows for the creation of lightweight, isolated, and scalable deployments. This is particularly beneficial in microservices architectures, where different components of the application can be deployed and scaled independently.Practical use cases: Worker Service can be used in a myriad of practical scenarios, such as sending batch emails, file processing, data imports/exports, or interacting with APIs for data synchronization. It’s also ideal for microservices that need to perform background work independently of user requests.

In summary, the Worker Service template in ASP.NET Core provides a robust foundation for building background services that can perform a wide range of tasks. Its integration with the broader .NET Core features, such as DI, configuration, and logging, makes it a powerful and flexible choice for developing background processes in your applications. Whether you’re processing jobs, polling resources, or performing scheduled tasks, Worker Service offers a structured yet flexible framework to build reliable and scalable background services.

Now that we understand the main aspects of the project templates available for ASP.NET Core projects, let’s move on to the next section, where we’ll explore the high-level aspects of the ASP.NET Core architecture and its features.

Exploring the ASP.NET Core architecture and its features

ASP.NET Core is a comprehensive framework designed for building modern, cloud-optimized, and internet-connected applications. Its architecture is modular, flexible, and designed to provide an optimized development framework for both web applications and APIs. Let’s delve into the ASP.NET Core architecture and its key features to understand what makes it a powerful choice for developers.

ASP.NET Core’s architecture is fundamentally modular, allowing applications to include only the necessary components and libraries, thereby reducing the application’s footprint and improving performance. This modularity is facilitated by the framework’s reliance on NuGet packages, which can be added or removed based on the specific needs of the application.

Startup and middleware in ASP.NET Core

The Startup class and middleware are foundational elements in the architecture of ASP.NET Core applications as they orchestrate the application’s behavior and its response to incoming HTTP requests. Understanding how these components interact provides insights into the backbone of ASP.NET Core’s processing pipeline.

The Startup class

The Startup class contains two main methods:

ConfigureServices: This method is where you add and configure services needed by your application. Services such as Entity Framework Core, MVC, Razor Pages, Identity, and others are registered here. DI is a first-class citizen in ASP.NET Core, and ConfigureServices is where the DI container is populated. This method allows your application to adhere to the principle of “explicit dependencies,” ensuring that components and services declare their dependencies transparently.Configure: After ConfigureServices runs, ASP.NET Core calls the Configure method. This is where you build the application’s request pipeline using middleware. Each middleware component can perform operations before and after the next component in the pipeline. The order in which middleware components are added is critical and defines the order of their execution for incoming HTTP requests and outgoing responses.

Middleware

Middleware in ASP.NET Core is software that’s assembled into an application pipeline to handle requests and responses. Each piece of middleware can perform operations before passing the request on to the next component in the pipeline or performing operations before the response is sent back to the client.

The following points illustrate the main aspects of the concept of middleware in ASP.NET Core projects:

Request pipeline: Middleware components form a chain of request delegates, where each component can perform operations asynchronously and decide whether to pass the request to the next component. If a middleware component doesn’t call the next delegate, it can short-circuit the pipeline, and no subsequent middleware is executed.Built-in middleware: ASP.NET Core comes with a set of built-in middleware components that you can use to enable functionality such as static file serving, routing, authentication, and session state. For example, the static files middleware serves static files and is often one of the first components in the pipeline, ensuring that requests for static files are handled without going through unnecessary processing.Custom middleware: You can also create custom middleware for more specific or specialized handling. Custom middleware is written by defining a class with an Invoke or InvokeAsync method that processes the HTTP request and calls the next middleware in the pipeline. This flexibility allows developers to extend the framework to suit their specific needs.Ordering: The order in which middleware components are added in the Configure method defines the order of their execution. This ordering is crucial because it can affect everything from security (ensuring authentication happens early in the pipeline) to functionality (ensuring MVC handling happens after the necessary preprocessing steps).Branching: The pipeline can be branched to configure different middleware components for different request paths. This can be achieved using the Map or MapWhen method, which provides fine-grained control over how requests are handled based on paths or conditions.

In summary, the Startup class and middleware in ASP.NET Core provide a robust and flexible way to configure how your application behaves and responds to HTTP requests. By understanding and utilizing these components effectively, developers can architect their applications to be modular, efficient, and maintainable, with clear control over the request handling pipeline.

DI in ASP.NET Core

DI is a design pattern that promotes loose coupling between components, making them more modular and testable. ASP.NET Core has built-in support for DI, allowing services to be registered and resolved throughout the application. Understanding how DI works in ASP.NET Core is crucial for developing applications that are easy to maintain and extend.

Core concepts of DI

The first concept we’ll cover is service registration. In ASP.NET Core, services are registered in the ConfigureServices method of the Startup class. This registration process maps interfaces or service types to concrete implementations. The framework provides different service lifetimes for registration, including Singleton, Scoped, and Transient, each defining how and when instances of the service are created and shared.

Now, let’s learn about service resolution. Once services have been registered, they can be injected into components, such as controllers, middleware, or other services, through their constructors. This is known as constructor injection, the most common method of DI in ASP.NET Core. The framework’s built-in DI container automatically resolves these services and their dependencies when the component is created.

In ASP.NET Core applications, services can be configured with distinct lifetimes, each defining the scope and duration of their availability within the application’s life cycle. These service lifetimes play a crucial role in determining how instances of services are created, shared, and disposed of, thereby impacting the application’s behavior, resource management, and overall architecture. The following lifetimes are available for configuration:

Singleton: Singleton services