How Angular Works Under the Hood?

Angular is a popular front-end web development framework that provides developers with a powerful and intuitive platform for building modern web applications. It’s a comprehensive framework that includes a wide range of features and tools, including data binding, dependency injection, and component-based architecture. In this blog post, we’ll take a deep dive into how Angular works under the hood.

Architecture of Angular

Angular components are reusable pieces of code that encapsulate the HTML, CSS, and JavaScript logic for a specific UI feature. Each component has its own template that defines its view and behavior, as well as its own styles and services.

The application components are arranged in a tree-like structure, where the root component represents the top-level component.

Angular uses a hierarchy of modules to organize the application into smaller and more manageable parts and to define the dependencies between different parts of the application. Each module encapsulates a set of related components, services, and other features.

Data Binding

One of the key features of Angular is its data binding mechanism, which enables the synchronization of data between the component and the view. There are four types of data binding in Angular:

1. Interpolation: The view in Angular uses interpolation to display data by embedding expressions in the HTML markup.
2. Property Binding: To set the value of an element’s property in the view, you can use property binding.
3. Event Binding: Allows you to handle events in the view, such as button clicks or form submissions.
4. Two-way Binding: By combining property binding and event binding, two-way binding establishes two-way communication between the component and the view.

Dependency Injection

Angular has a dependency injection mechanism that efficiently manages dependencies between different parts of the application. This mechanism follows the design pattern of dependency injection where a component’s dependencies are injected into it instead of being instantiated within it.This allows for greater flexibility, testability, and scalability of the application.

Angular’s dependency injection system works by using providers, which are responsible for creating and providing instances of the dependencies. Providers can be defined at the component level, the module level, or the application level. The dependency injection system uses the providers to resolve the dependencies of the components at runtime.

Change Detection

Angular uses a change detection mechanism to track changes to the component’s data and to update the view accordingly. Angular’s change detection system works by comparing the current state of the component’s data with its previous state and the state of its child components. If a change is detected, Angular updates the view to reflect the new state.

Angular’s change detection system uses zones, which are execution contexts that enable the monitoring of asynchronous operations. Zones provide a way to intercept asynchronous operations, such as setTimeout or XMLHttpRequest, and to execute additional code before or after the operation.

Conclusion

Angular is a powerful and comprehensive framework that provides developers with a robust platform for building modern web applications. Its component-based architecture, data binding mechanism, dependency injection system, and change detection mechanism are some of the key features that make it so popular among developers. Understanding how Angular works under the hood is essential for mastering the framework and building high-quality and scalable applications.

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