Angular for Modern Web Development: A Complete Guide

1. Advantage of Angular 8:

   • Enhanced performance with Ahead-of-Time (AOT) compilation.
   • Improved Ivy renderer, which is smaller, faster, and more extensible than the View Engine.
   • Better error handling and debugging.
   • Support for TypeScript 3.4/3.5 out of the box.
   • Enhanced internationalization (i18n) and locale ID format simplification.
   • Server-side rendering with Angular Universal still supported and improved.
   • Angular Elements for building components to be used outside of an Angular app.
   • Built-in service workers for background sync, push notifications, and offline caching.

2. Disadvantage of Angular 8:

   • Large project size can be a disadvantage in resource-constrained environments.
   • Steeper learning curve compared to other frameworks/libraries.
   • Might be overkill for small projects where a simpler solution like Vue or React might suffice.
   • Frequent updates and changes may lead to a steeper adoption curve.

3. Angular 8 File Structure:

   An Angular 8 application typically has the following directory structure:

   my-app/
   ├── e2e/                     # End-to-end tests
   │
   ├── src/                        # Source files
   │   ├── app/                      # App components & modules
   │   │   ├── app.component.ts
   │   │   ├── app.module.ts
   │   │   └── ...
   │   ├── assets/                   # Static file assets (image, SCSS, etc.)
   │   ├── environments/          # Environment-specific config values
   │   │   ├── environment.ts
   │   │   └── environment.prod.ts
   │   ├── models/                  # Application models
   │   ├── services/                # Shared services and APIs
   │   └── ...
   │
   ├── src/main.ts                   # Bootstrap the application (entry point)
   ├── src/polyfills.ts              # Modern browser polyfills (if any)
   ├── angular.json                  # Angular app configuration file
   └── ...
   

4. Angular 8 components:

   Components are the core building blocks of an Angular application. Each component manages a portion of the user interface, encapsulates its data and behavior, and communicates with other components. They form a tree-like hierarchy starting from the root AppComponent.

5. Angular 8 CLI Commands:

   Angular CLI provides a set of commands to generate, build, test, and serve Angular applications. Some common commands include:

   ng new my-app           # Create a new project
   ng serve                 # Run the app in development mode
   ng build                 # Compile the app for production
   ng generate component my-component  # Generate a new component
   ng test                  # Run unit and end-to-end tests
   ng lint                   # Lint all files in the current workspace
   

6. Angular 8 with Bootstrap:

   Bootstrap is a popular CSS framework that can be easily integrated into Angular applications to style the components.

   • To install Bootstrap, you can use npm or yarn:

     npm install bootstrap --save
     

     • Then, include Bootstrap in your angular.json file or import it directly into your global styles (styles.scss or styles.css).

7. Angular 8 Routing:

   Angular's router enables navigation from one UI component to another based on user actions or application state changes. It manages a set of active routes, permits navigation requests matched against the current route(s), and provides services for reacting to route changes.

8. Angular 8 Directives:

   Angular directives are markers on HTML elements that tell Angular’s compiler how to treat those elements. They help in creating dynamic, data-driven templates. The main types of directives are:

   • Component: encapsulate code into reusable components and manage their own scope.
   • Structure: alter the DOM by adding or removing DOM elements or attributes.
   • Attribute: change the appearance or behavior of theDOM based on expression evaluation.

9. Angular 8 Services:

   Services are classes that provide data and functionality to components and other services. They can be used to implement complex behaviors or to share data between components.

10. Angular 8 Guards for Routing:

    Angular guards are interfaces that you apply to routes (via route configuration) or route parameters (via the CanActivateChild, CanLoad, or CanActivate methods on route configurations). They're used to determine whether a user should be allowed to view or interact with a given routed-to view at a particular time.

11. Angular 8 Forms:

    Angular supports two different approaches to handling form data: Reactive Forms and Template-Driven Forms. Each has its own set of advantages, and the choice between them depends on your application's requirements.

12. Angular 8 Change Detection:

    Angular implements change detection mechanisms that detect and apply view updates as data in your application changes. It's a core part of Angular's data-binding feature, allowing you to declaratively link your model (data) with the view (UI).

13. Angular 8 Observables and RxJS:

    Observable is a design pattern that represents asynchronous data streams and the operations performed on those streams. Angular often uses RxJS (Reactive Extensions for JavaScript) to handle observables.

14. Angular 8 Internationalization (i18n):

    i18n enables you to create applications that support multiple languages, making your app accessible to a wider audience. Angular achieves this through the use of language-specific files and special pipes like LocaleIdPipe.

15. Angular 8 Server-Side Rendering (SSR):

    SSR allows you to pre-render your Angular application on the server side, which can significantly improve the loading performance of your app, especially for users with slower devices or unreliable internet connections.

16. Angular 8 Universal is a version of SSR that uses Node.js on the server and can serve the same application to both browser and server-side clients without rewriting the codebase.

17. Angular 8 new Features and Changes:

• The Ivy rendering platform, which is now the default compiler for Angular applications. It provides significant performance improvements.
• Improved change detection, making it faster and more efficient.
• Enhancements to the core APIs, including HttpClient, making network requests more robust and easier to handle.
• New and improved Angular Material components.
• The introduction of Angular Console, a tool that integrates with your development workflow for more efficient management of your project lifecycle.

These features and improvements make Angular 8 a powerful framework for building enterprise-grade applications with the need for high performance, robustness, and scalability.