Angular Fundamentals: Essential Interview Quiz Quiz

Explore key concepts of Angular with this focused quiz designed for interview preparation. Assess your understanding of Angular architecture, components, data binding, services, and dependency injection through practical, scenario-based questions.

1. Component Structure in Angular

   In Angular, what is the primary purpose of a component’s decorator, such as @Component, when defining a new component?

   1. To declare routing paths for component navigation
   2. To link external modules to the component automatically
   3. To import services into the component directly
   4. To specify metadata like selector, template, and styles for the component

   Explanation: The component decorator provides metadata that tells Angular how to process the class, including its selector, template, and styles, which are essential for rendering the component. Linking external modules and importing services are achieved through other mechanisms such as NgModule imports or constructor injection. Declaring routing paths is done using routing configuration files, not directly in the component decorator.

2. Data Binding Techniques

   Which Angular data binding technique enables real-time synchronization of data between the component class and the view, such as updating an input field as the user types?

   1. Event delegation binding
   2. One-way output binding
   3. Two-way data binding
   4. Service-based binding

   Explanation: Two-way data binding ensures that changes in the component class update the view and vice versa, which is commonly used with input elements for real-time updates. One-way output binding passes data only from child to parent components. Service-based binding refers to sharing data via services, which does not directly synchronize properties with the view. Event delegation binding is not a recognized Angular data binding type.

3. Modules and Application Structure

   If you want to organize reusable features and group components, directives, and services together in Angular, which structure should you utilize?

   1. Components
   2. Providers
   3. Pipes
   4. NgModule

   Explanation: NgModule is the organizational unit in Angular that bundles related components, directives, services, and more, allowing code reusability and modularization. Components are single UI elements rather than grouping constructs. Pipes are used to transform outputs in templates, not to organize features. Providers register services for dependency injection but do not group structural elements.

4. Angular Services Purpose

   When building an Angular application that requires shared business logic or state management across multiple components, which construct should you use?

   1. Service
   2. Selector
   3. Directive
   4. Pipe

   Explanation: Services are designed to encapsulate shared logic and state, and are injected into components as needed, making them ideal for sharing data or business logic. Directives modify the behavior or appearance of elements. Pipes transform visible output in templates but are not meant for logic or state management. A selector is a property that allows Angular to identify directives or components in templates, not a tool for sharing logic.

5. Dependency Injection Mechanism

   Which feature in Angular makes it possible to inject services or other dependencies into components and directives automatically, thereby improving code modularity and testability?

   1. Dependency injection
   2. Shadow binding
   3. View encapsulation
   4. Zone context

   Explanation: Dependency injection is a core feature that allows Angular to provide services and other dependencies to components or directives seamlessly, improving modularity and facilitating testing. View encapsulation deals with scoping styles to components. Zone context manages change detection but does not inject dependencies. Shadow binding is not a standard Angular feature related to dependency management.