Angular Interview Practice

What are directives in Angular primarily used for?

1. To manage application routing

2. To add behavior to elements in the DOM

3. To handle form validation

4. To create services for data sharing

The correct answer is: To add behavior to elements in the DOM

Directives in Angular are primarily used to extend HTML capabilities by adding behavior to elements in the Document Object Model (DOM). They allow developers to manipulate the rendering and functionality of elements efficiently. This includes altering the appearance, structure, or behavior of those elements based on certain conditions or actions. For instance, directives can be used to create reusable components that encapsulate specific functionality or visual elements. Common examples include structural directives like *ngFor and *ngIf, which dynamically alter the DOM based on the underlying application state or conditions. Additionally, attribute directives can be applied to modify the behavior of specific elements, such as changing styles or handling events. The other options, while associated with Angular, are not the primary purpose of directives. Managing application routing is handled by the Angular Router, handling form validation is done using forms and validation directives, and creating services for data sharing is done through Angular's dependency injection system, rather than through directives. Thus, the specific role of directives is to enhance and manipulate the DOM effectively.