Answers to the Best 21 Angular Interview Questions of 2023

Angular is widely popular as a web development framework, thanks to its various applications. With Angular, users can develop dynamic single-page applications and create user interfaces for mobile and desktop apps. When it comes to job interviews, questions on Angular typically touch on the framework’s ability to create visually appealing user interfaces, optimise app performance, and the advantages and disadvantages to using Angular. Interviewees should therefore have a solid grasp of Angular fundamentals and be able to talk knowledgeably about similar projects they’ve tackled. Additionally, familiarity with the latest trends in web development is a bonus as it helps to explain what benefits Angular can afford the user.

Keep reading to discover the answers to these questions.

Introduction

The number of individuals around the globe who use the internet and mobile applications for almost everything in their lives is estimated at over one billion. The reason these applications are so popular is that users can have a smooth experience while utilizing them.

Have you ever wondered how developers manage to include so many features in mobile applications? Much of it is due to the widespread use of well-known web frameworks. There are many web-based frameworks and tools available to streamline the app-building process.

Angular is unmatched when it comes to developing the front end of websites. This well-known JavaScript framework is a go-to tool for developers around the globe who need to create dynamic web applications that work across various devices and platforms. Thanks to its powerful features and ease of use, Angular is a top tool for web developers.

What is Angular?

Managed by Google, Angular is an open-source JavaScript framework designed primarily for creating single-page applications. By using this framework, programmers can take advantage of its versatile and feature-rich capabilities while working on a consistent platform.

Leverage the specialised structure of this framework to construct easily maintainable apps.

Square and obtuse design explained

Angular is an essential Model-View-Controller (MVC) framework in web development. This framework organises the development process and enables two-way data binding within the Document Object Model (DOM). Below are the six components essential for an Angular application:

  1. Modules:

    To start with an Angular app, the first step is to import the root module – AppModule.
  2. Components:

    Each segment of the app defines a class that contains both data and logic for that particular part.
  3. Templates:

    The Angular markup is employed in conjunction with HTML in the Angular template to pre-render alterations to HTML components.
  4. Metadata:

    Angular uses metadata to offer supplementary information about classes, which assists the framework in determining how to handle them. By adding a layer of decoration to a class, its expected behavior can be adjusted to suit the application’s specific needs.
  5. Services:

    In software development, creating a service class is critical when components must share data or logic that is not related to the view. The service class and the @Injectible decorator are inextricably linked, and they must be used together to ensure that data and logic are transferred correctly.
  6. Dependency Injection:

    This feature enables developers to streamline their component classes without compromising their functionality. Instead of relying on traditional techniques for gathering information, such as polling remote servers, asking for user input, or logging directly to the terminal, dependency injection delegates these activities to various services.

Frequently Asked Questions and Answers for Angular Interviews

  1. What is meant by “one page applications” in software context?

    “Single-Page Applications” are a type of web application that operates on a single HTML page (SPAs).

    Angular employs Asynchronous JavaScript and XML (AJAX) to modify HTML components dynamically, which enables the development of Single-Page Applications (SPAs). SPAs create the impression of a native desktop application, rather than a traditional website.

    By utilising the abilities of Angular, users can be presented with dynamic data in an HTML template. String Interpolation, for example, allows developers to retrieve data from a module and combine it into an HTML template.
  2. What is the process of writing an Angular Decorator?

    Decorators are functions that can be assigned to different components of a class, such as a method, parameter, or property, by introducing the @ symbol before their name. These functions take in the context of the class, parameter, or method, and produce a modified or replaced version of the target. By employing decorators, developers can code more concisely and effectively.

    Syntax: It’s a @() function that accepts arguments.
  3. What is the role of [(ngModel)]?

    The ngModel directive enables user input to be bound to a variable, the selection of text areas, and the storage of user information. Moreover, this directive is typically employed for the validation of forms.
  4. What are the fundamental parts of an Angular application?

    An Angular application is made up of multiple fundamental components such as modules, components, property binding, templates, structural directives, dependency injection, services, and routing. These elements are critical to building a functional application that can be easily updated and maintained. Modules offer the necessary organisation structure for the code, whereas components are the basic building blocks of the application. Property binding facilitates communication between the component class and the template. Templates are used to provide the user interface, and structural directives offer ways to modify the DOM structure. Dependency injection is utilised to provide services to the components, while routing is an approach to defining the application’s response to user actions. All of these components are vital to the development of an Angular application.
  5. What is the exact meaning of change detection?

    Change detection is a method that Angular employs. If data changes, change detection is responsible for re-rendering the display.
  6. What are pipes in Angular?

    In Angular, pipes are simply functions that are utilised to change an input value according to the developer’s requirements. By combining several pipes, a user can establish a series of functions. The pipe is symbolised by the ‘|’ symbol.
  7. Let’s start by defining Bootstrapping in Angular.

    In Angular, the term “bootstrapping” is utilised to describe a technique for launching applications.
    Each Angular application must have one module, known as the root module, which is “bootstrapped” when the application is launched for the first time. This root module is typically named AppModule and is represented by a class that has been decorated with the @NgModule decorator. This class is usually placed after the import statements.
  8. Which method is called when a TypeScript object is created?

    When a TypeScript object is created, the constructor function is invoked.
    Syntax: Constructor() {}
  9. Explain the process of enabling communication between Parent and Child components in Angular.

    For transferring data between a Parent and a Child component in Angular, the @Input decorator in the Child component is utilised. If there is a requirement to transmit information from the Child to the Parent, the @Output decorator in the Child component can be employed to enable such communication.
  10. If someone is unfamiliar with Angular, what is CLI?

    The Angular CLI (Command Line Interface) is a command shell tool that facilitates the creation, scaffolding, management, and running of Angular applications. You can visit Angular CLI to learn more about it.
  11. What does the term “Transpiling” mean in Angular?

    Transpiling is the process of transforming program code written in one computer language to another language. In Angular, this typically refers to converting TypeScript, which is a statically-typed superset of JavaScript, into plain JavaScript. This conversion improves code readability and makes the code compatible with various browsers and platforms.

    Coding for an Angular application can be done using TypeScript or any other language that can be transpiled into JavaScript, such as Dart. This process is simple and straightforward, and is a natural part of the development process.
  12. Can you provide a definition of SPA in the context of Angular?

    Single page applications (SPAs) are web applications that are accessed via a web browser and operate on a single HTML page. In response to user input, certain areas of the page are dynamically updated, without having to reload or switch pages. Following the provided instructions is critical to ensuring that your site runs seamlessly and loads quickly.
  13. What is meant by an Angular directive?

    Directives are classes that provide additional functionalities to components, which can be advantageous for Angular applications. Forms, styles, lists, and user presentations can all be efficiently managed by utilising the pre-built directives present in Angular.
  14. What is the meaning of “Change Detection,” and what is the procedure for detecting changes in Angular?

    When a model and view have been synchronised and brought into alignment, it is referred to as change detection. Even with two-way binding using ngModel, the data flow in Angular remains one-way, as it only represents a convenient form of the underlying one-way flow.

    The process for detecting changes is also unidirectional, flowing upwards from the foundation to the top. This one-way flow of information means that data does not flow in the opposite direction. An Angular application is comparable to a tree with distinct modules, each of which has its own child with no connection between the parents and children. This one-way data flow obviates the need for a $digest loop.
  15. What are the two techniques used to identify and track changes in Angular?

    Angular provides two distinct methods for detecting changes: Default and OnPush.

    If all components employ the default method, then the entire tree is scanned for changes.

    When users adopt a proactive approach, they communicate their intent to follow best practices for improved performance to Angular. This communication informs Angular that the user component depends solely on user-supplied data, and any object transmitted to it must be treated as immutable. For more information on Angular’s navigable and default routes, you can read our blog post.
  16. What happens to the display when the data model is updated outside the “Zone” in Angular?

    To monitor the entire component tree for changes, ApplicationRef.prototype.tick is used.

    NgZone.prototype.run can be used to initiate change detection across the entire tree. The run method invokes the tick method in the background, taking the function to be executed as an argument.

    Use the ChangeDetectorRef.prototype.detectChanges function to start keeping track of changes in both the current component and its descendants.
  17. In Angular, what does “lazy loading” refer to?

    Developers frequently utilise lazy modules to divide large amounts of code into smaller sections. It has been discovered that not all of the application’s code is required to be loaded in the browser version. Thus, the module must make use of lazy loading to retrieve the code into the browser before the route transition.

    The following is an example of a module that utilises lazy loading:
    Path: “example,” LoadChildren: “./example/example.module#ExampleModule,” Component: “PublicComponent”
  18. What is the goal of the Core and Shared modules in Angular?

    To ensure efficient performance of an application, it is commonplace to preserve frequently used modules, components, directives, pipes, and related objects in a single, shared module. This enables a more efficient utilization of these components, as they can be accessed from multiple modules without the need for duplication.

    Core modules, on the contrary, are used by developers to store global singletons of services that are utilised throughout the entire application.
  19. What factors should be considered when attempting to maximise an Angular 6 application’s performance?

    Here are some of the tactics that can be employed to boost the speed of an Angular 6 application:
    • Tree Tremors that Cause Anxiety
    • Lazy Loading
    • Separating devDependencies and dependencies
    • The Full A.O.T. (Ahead-of-Time)
    • The software was grouped together and presented in a negative light.
    • Utilizing OnPush and TrackBy to avoid computing template values
    • Removing Inessential Import Statements and External Libraries
  20. What are some ways to ensure the safety of an Angular application?

    The following suggestions can help safeguard an Angular application:
    • Ensure that your web application is the origin of all requests and not any other site.
    • Validating the Integrity of Each Data Input
    • Replace DOM APIs with Angular’s Template System
    • Consistently Adhere to Content Security Policies
    • Authenticate All Information Using Server-Run Code
    • If Compiling Templates, Select an Option That Performs Offline
    • Avoid Linking to any External Websites within the Application
    • Stay Up-to-Date on Library and Framework Upgrades
  21. What is the difference between unit testing and full system testing?

    During unit testing, individual pieces of code are tested to ensure they function correctly.

    Full system testing, on the other hand, involves testing the entire system or program from start to finish. This is to guarantee the program or system works properly by simulating real user interactions. End-to-end testing provides confidence that there are no errors in the software and that it performs as intended.

Conclusion

To determine how an individual can support your company, it’s crucial to thoroughly investigate their thought process and pose pertinent follow-up questions. One approach to accomplish this could be to incorporate particular inquiries into your interviewing procedure.

Although numerous candidates often apply for developer positions, it is crucial to ask interview questions of varying difficulty levels to prevent the process from becoming monotonous and repetitive. You can find a list of relevant interview questions and their ideal answers for React JS in 2023 here.

If you are encountering issues with recruiting and managing developers, you should consider using Works. With Works, the entire recruitment process can be completed in three to five days, potentially saving you up to fifty hours of work. Furthermore, Works has an extensive pool of over 1.5 million programmers from 150+ different countries.

FAQs

  • What are some popular uses for Angular?

    Angular is a platform and framework for building client-side single-page applications using HTML and TypeScript.
  • What are some typical Angular interview questions?

    Here are some common questions that may be raised during an Angular-related interview:
    • Firstly, let’s clarify what we mean by “single page applications.” Explain how they operate in Angular.
    • Can you outline the essential syntax for an Angular Decorator?
    • Can you explain the function of [(ngModel)]?
    • What are the basic components of an Angular application?

Join the Top 1% of Remote Developers and Designers

Works connects the top 1% of remote developers and designers with the leading brands and startups around the world. We focus on sophisticated, challenging tier-one projects which require highly skilled talent and problem solvers.
seasoned project manager reviewing remote software engineer's progress on software development project, hired from Works blog.join_marketplace.your_wayexperienced remote UI / UX designer working remotely at home while working on UI / UX & product design projects on Works blog.join_marketplace.freelance_jobs