If you’re looking for an Angular 9 tutorial, you’ve come to the right place. Angular 9 features some improvements and new features. This tutorial covers Angular components, HttpClient, dependency injection, and Angular Forms. This tutorial also includes new Angular features like HttpClient.
Angular components
Angular uses component metadata to identify a component in a template. This metadata corresponds to an HTML tag that is used by the parent component. It allows you to define markup for a component. A component can be used to define a host view or a set of related components.
Angular 9 introduces several improvements and changes for developers. For example, Angular’s compiler now has better support for phantom variables. Phantom variables, or variables that are not cited in a template, can threaten applications. Angular 9 has a way to detect these phantom variables without compromising performance.
This new version of Angular offers more optimization options for the development of mobile apps. Compared to Angular 8, Angular 9 improves performance. By reducing the bundle size, developers can create smaller applications that load more quicker. This can be beneficial because almost half of the website traffic in the world comes from mobile devices. Further, a large portion of these users is located in areas where the internet connection is slow. The smaller the bundle size, the better the experience for mobile users.
Angular dependency injection
Angular 9 dependency injection is a powerful new way to manage the relationship between components and services. The idea behind this technique is to isolate services from other components, which makes them testable and editable independently. To use dependency injection, you must create a new Angular service and a TypeScript interface. You must also create a model for validating the data returned by the product’s service. Lastly, you must define a provider for your service, specifying the root injector.
The injector creates dependencies and injects them whenever needed. The injector creates tokens representing the objects that depend on the components. When a dependency is needed, it resolves the token, which is a key-value pair.