Common Angular Interview Questions and Answers for Experienced Developers | Helpful Angular Interview Questions from @uidevguide

Angular is a popular front-end framework used for building dynamic web applications. If you are looking to land a job as an Angular developer, you may encounter some experienced interview questions during the interview process. In this tutorial, we will provide you with a list of common Angular experienced interview questions and answers to help you prepare for your interview and increase your chances of success.

1. What is Angular and how does it differ from other front-end frameworks?

Angular is a front-end framework developed by Google for building single-page web applications. It is based on TypeScript, a superset of JavaScript, and follows the MVC (Model-View-Controller) architecture pattern. Angular differs from other front-end frameworks such as React and Vue.js in that it provides a more comprehensive solution for building web applications, including features such as two-way data binding, dependency injection, and built-in routing.

1. What is the difference between AngularJS and Angular?

AngularJS, also known as Angular 1, is the first version of Angular released by Google. It uses JavaScript and follows the MVC architecture pattern. Angular, on the other hand, refers to Angular 2 and later versions, which are built on TypeScript and follow the component-based architecture pattern. Angular offers improved performance, better code organization, and a more modular and scalable codebase compared to AngularJS.

1. What are the key features of Angular?

Angular offers a wide range of features that make it a powerful front-end framework for building web applications. Some key features of Angular include:

• Two-way data binding: Automatically synchronizes the data between the model and the view in the application.
• Dependency injection: Provides a way to manage dependencies between different components in the application.
• Directives: Allows you to extend HTML with custom attributes and behavior.
• Services: Used to encapsulate reusable code and business logic.
• Routing: Enables navigation between different views of the application.
• Forms: Provides support for creating and validating forms in the application.
• HttpClient: Allows you to make HTTP requests and handle responses in the application.

1. What is NgModule in Angular?

NgModule, short for Angular Module, is a decorator function that defines a module in an Angular application. Modules are used to organize the application into cohesive blocks of functionality and can contain components, directives, services, and other Angular features. Each Angular application has at least one root module, which is typically defined in the app.module.ts file. Modules help to manage the dependencies between different parts of the application and provide a way to modularize the codebase for better organization and scalability.

1. What is Angular CLI and how is it used?

Angular CLI (Command Line Interface) is a command-line tool provided by Angular for creating, building, and maintaining Angular applications. It simplifies the development process by generating boilerplate code, managing dependencies, and providing tools for building, testing, and deploying the application. To create a new Angular project using Angular CLI, you can run the following command:

ng new my-app

This will create a new Angular project in a directory named ‘my-app’ and set up the necessary configuration files and folder structure. You can then use Angular CLI commands such as ng generate component or ng build to generate code and build the application.

1. What is a Resolver in Angular?

A Resolver is a service in Angular that is used to fetch data before the component is rendered. Resolvers are often used in Angular applications to ensure that the required data is available before displaying the component to the user. This can be useful for preloading data from a server, performing authentication checks, or handling route guards. To create a Resolver in Angular, you can define a class that implements the Resolve interface and implements the resolve method to fetch the data asynchronously.

1. What is Angular Universal and why is it used?

Angular Universal is a server-side rendering solution for Angular applications that allows you to render the application on the server and send the pre-rendered HTML to the client. This can improve the performance and SEO of the application by reducing the time to first paint and making the content accessible to search engines. Angular Universal can be used to generate static HTML files for static site hosting or to render the application on the server to improve the initial load time for users. It can be integrated with different server-side technologies such as Node.js, Express, or ASP.NET Core.

1. How does Change Detection work in Angular?

Change Detection is a mechanism in Angular that tracks and updates the DOM (Document Object Model) based on changes in the application’s data. Angular uses a hierarchical tree of change detectors to detect changes in the application’s data and update the corresponding views accordingly. When a change occurs in the application data, Angular triggers a change detection cycle that updates the views and propagates the changes throughout the application. Change Detection can be optimized using different strategies such as OnPush change detection, Immutable.js, or custom change detection strategies to improve the performance of the application.

1. What is AOT (Ahead-of-Time) compilation in Angular?

AOT (Ahead-of-Time) compilation is a technique in Angular that compiles the application code during the build process rather than at runtime in the browser. This can help to improve the performance of the application by reducing the initial load time, optimizing the size of the bundle, and detecting errors earlier in the development process. AOT compilation converts the application code into highly optimized JavaScript code that is ready to be executed in the browser without the need for a separate compilation step. This can result in faster startup times, smaller bundle sizes, and better overall performance for Angular applications.

1. How does Dependency Injection work in Angular?

Dependency Injection is a design pattern in Angular that enables you to inject dependencies into components, directives, services, and other parts of the application. Dependency Injection is used to manage the dependencies between different parts of the application and facilitate the creation of modular, reusable code. In Angular, dependencies are registered with Angular’s dependency injection system and injected into the components or services that need them. This can help to decouple the components, improve testability, and make the codebase more maintainable and scalable.

In conclusion, these are just a few examples of common experienced interview questions you may encounter when interviewing for an Angular developer position. By understanding these concepts and practicing your skills, you can confidently answer these questions and demonstrate your expertise in Angular development. Good luck with your interview preparation!