Tutorials – ASP.Net C#

Chapter 5 – ASP.NET Core

5.1 Introduction to ASP.NET Core

ASP.NET Core is a modern, cross-platform, open-source framework developed by Microsoft for building web applications. It is designed to address the shortcomings of its predecessors while introducing a wide range of improvements and new features. ASP.NET Core offers the following key benefits:

• Cross-Platform Compatibility: ASP.NET Core is cross-platform and can run on Windows, macOS, and Linux. This versatility allows developers to choose their preferred development environment.

• High Performance: The framework is optimized for high performance, making it suitable for building scalable and responsive web applications. It boasts improved request processing and lower memory consumption.

• Modularity and Flexibility: ASP.NET Core is modular, meaning you only include the components your application needs. It provides flexibility to build lightweight APIs or full-featured web applications.

5.2 Key Advantages of ASP.NET Core

ASP.NET Core offers several advantages over its predecessors, including ASP.NET Web Forms and ASP.NET MVC:

• Cross-Platform Support: ASP.NET Core runs on multiple platforms, reducing development and hosting constraints. Developers can use their preferred operating system for development and deployment.

• Improved Performance: ASP.NET Core is optimized for performance, offering faster response times and reduced memory consumption. It benefits from a rewritten request pipeline and improved runtime.

• Enhanced Security: ASP.NET Core provides built-in security features such as automatic request validation, improved authentication and authorization mechanisms, and protection against common security threats.

5.3 ASP.NET Core Architecture

• Request Pipeline: Explore the request pipeline in ASP.NET Core, which consists of middleware components that process HTTP requests and responses. The pipeline is highly configurable, allowing you to customize request handling.

• Middleware: Middleware components are the building blocks of the request pipeline. Each middleware component performs a specific task, such as routing, authentication, or handling static files. Middleware components can be added, removed, or reordered to modify the request processing flow.

• Kestrel Web Server: Understand the role of the Kestrel web server, the default server for ASP.NET Core applications. Kestrel is a lightweight, cross-platform server optimized for performance.

• Hosting Model: Explain the ASP.NET Core hosting model, which separates the application from the web server. This separation provides flexibility and allows ASP.NET Core applications to run in various hosting environments.

5.4 Creating a Basic ASP.NET Core Project

• Project Creation: Guide readers through the process of creating a basic ASP.NET Core project using either Visual Studio or the .NET CLI (Command-Line Interface). Provide instructions for selecting the project template and specifying the project name.

• Project Structure: Explain the structure of an ASP.NET Core project, including folders for controllers, views, models, and configuration. Familiarize readers with key files and directories.

• “Hello World” Example: Create a simple “Hello World” ASP.NET Core application to illustrate the basics of routing, controllers, views, and the Startup.cs configuration file.

5.5 Middleware in ASP.NET Core

• Middleware Components: Delve deeper into middleware components in ASP.NET Core. Explain how each middleware component in the request pipeline processes requests and responses.

• Middleware Configuration: Describe how to configure middleware components in the Startup.cs file using the UseMiddlewareName methods. Discuss the order in which middleware components are executed.

5.6 Controllers and Views in ASP.NET Core

• Controllers: Highlight the role of controllers in ASP.NET Core, which are responsible for handling HTTP requests. Controllers define action methods that respond to specific URLs and interact with models and views.

• Views: Explain views, which are responsible for rendering HTML content to the client. Views can use view engines like Razor to generate dynamic HTML. Show how to create views and render data in them.

5.7 Dependency Injection in ASP.NET Core

• Dependency Injection: Introduce dependency injection (DI) in ASP.NET Core, which is a built-in feature for managing dependencies. Explain how DI promotes modularity and testability by providing services and components when needed.

• Service Registration: Demonstrate how to register services and components with the built-in DI container. Register services in the Startup.cs file and show how to resolve them in controllers and other classes.

5.8 Routing and Attribute Routing in ASP.NET Core

• Routing Overview: Explore routing in ASP.NET Core, which maps URLs to controller actions. Discuss the structure of routes and route templates.

• Route Configuration: Explain how to configure routes in the Startup.cs file using the UseEndpoints method. Provide examples of custom route definitions and route parameters.

• Attribute Routing: Introduce attribute routing, a convenient way to define routes using attributes like [Route]. Explain how attribute routing simplifies route configuration and customization.

5.9 Model Binding and Validation in ASP.NET Core

• Model Binding: Delve into model binding in ASP.NET Core, a process that automatically maps HTTP request data to action method parameters. Explain model binding for simple types and complex objects.

• Model Validation: Discuss model validation and the use of data annotations to enforce data validation rules. Handle validation errors and provide user-friendly error messages in views.

5.10 Razor Pages

• Razor Pages Overview: Introduce Razor Pages, a lightweight alternative to controllers and views in ASP.NET Core. Explain how Razor Pages simplify page-focused scenarios and reduce boilerplate code.

• Creating Razor Pages: Create a basic Razor Pages application to illustrate the usage of Razor Pages. Define Razor Pages, handle HTTP requests, and render dynamic content.

5.11 ASP.NET Core Identity

• Identity Framework: Explore ASP.NET Core Identity, a framework for managing user authentication and authorization. Discuss user registration, login, and role-based authorization.

• Integration: Show how to integrate ASP.NET Core Identity into an ASP.NET Core application. Configure Identity services, create user accounts, and secure controllers and actions using authorization.

5.12 Key Takeaways

• Summary: Summarize the key concepts covered in this chapter, including ASP.NET Core architecture, middleware, controllers, views, dependency injection, routing, model binding, Razor Pages, and ASP.NET Core Identity.

5.13 Next Steps

• Preview: Give readers a glimpse of the topics and chapters to come in the tutorial.
• Encouragement: Encourage readers to explore advanced aspects of ASP.NET Core and start building real-world web applications.

Tips: This chapter provides a comprehensive introduction to ASP.NET Core, covering its key features, architecture, and advantages over previous ASP.NET frameworks. It also guides readers through the process of creating a basic ASP.NET Core project and introduces essential topics such as middleware, controllers, views, dependency injection, routing, model binding, Razor Pages, and ASP.NET Core Identity.