If you’re planning to become an Angular developer, you’ll have to ace your interviews. If you want to ace your interviews, you’ll have to be thorough in your understanding of both basic and advanced Angular concepts. In this article, we’re going to look at Angular questions that you can expect during an interview. Show Remember, In addition to theoretical questions, you will be asked some coding questions. We list a mix of both basic and advanced Angular interview questions here, which should give you a solid foundation for the interview. First, we cover basic Angular interview questions. After that, we switch to more advanced questions. These interview questions on Angular should give you the theoretical knowledge to prepare for an interview, but of course you want some to get some coding practice in as well. Basic Angular Interview Questions1. What is Angular?Angular is a TypeScript-based open-source web application framework, developed and maintained by Google. It offers an easy and powerful way of building front-end web-based applications. Angular integrates a range of features like declarative templates, dependency injection, and end-to-end tooling, that facilitate web application development. 2. Why was Angular introduced as a client-side framework?Traditionally, VanillaJS and jQuery were used by developers to develop dynamic websites. As websites became more complex, with added features and functionality, developers found it increasingly hard to maintain the code. Furthermore, there was no provision of data handling facilities across the views by jQuery. Angular was built to address these issues, making it easier for developers by dividing code into smaller bits of information that are known as Components in Angular. Client-side frameworks permit the development of advanced web applications like SPAs which, if developed by VanillaJS, is a slower process. 3. What are some features of Angular?There are several features of Angular that make it an ideal front-end JavaScript framework. Some of the most important ones are:
Recommended Angular Course4. State some advantages of Angular over other frameworks.Some of Angular’s advantages over other frameworks are:
5. What is the difference between Angular and AngularJS?The differences between Angular and AngularJS are stated as follows:
Yes, we can, with Angular Universal. The benefits of using Angular Universal are:
7. Explain Dependency Injection.Dependency injection is an application design pattern that is implemented by Angular and forms the core concepts of Angular. Dependencies in Angular are services that simply have some functionality. Components and directives in an application may need these functionalities. Angular provides a smooth mechanism by which these dependencies are injected into components and directives. 8. What are services in Angular?Singleton objects in Angular that get instantiated only once during the lifetime of an application are called services. An Angular service contains methods that maintain the data throughout the life of an application. The primary intent of an Angular service is to organize as well as share business logic, models, or data and functions with various components of an Angular application. The functions offered by an Angular service can be invoked from any Angular component, such as a controller or directive. 9. What are the advantages and disadvantages of using Angular?The following table explains the advantages and disadvantages of Angular: Advantages Disadvantages Can add custom directives Complex SPAs can be inconvenient and laggy to use due to their size Exceptional community support Dynamic applications do not always perform well Follows the MVC pattern architecture Learning Angular requires time and effort Offers support for static template and Angular template Support for two-way data binding Supports dependency injection, RESTful services, and validations 10. What are some features of Angular 7?Unlike the previous versions of Angular, the 7th major release comes with the splitting of @angular/core. This is done in order to reduce the size. Not every module is required by an Angular developer. Therefore, in Angular 7 each split of the @angular/core will have no more than 418 modules. Angular 7 features drag-and-drop and virtual scrolling. Lastly, it also has a new and enhanced version of the ng-compiler. 11. What is string interpolation in Angular?Also referred to as mustache syntax, string interpolation in Angular refers to a special type of syntax that makes use of template expressions in order to display the component data. These template expressions are enclosed within double curly braces i.e. {{ }}. The JavaScript expressions that are to be executed by Angular are added within the curly braces and the corresponding output is embedded into the HTML code. Typically, these expressions are updated and registered like watches as a part of the digest cycle. 12. Explain Angular Authentication and Authorization.The user login credentials are passed to an authenticated API, which is present on the server. Post-server-side validation of the credentials, a JWT (JSON Web Token) is returned. The JWT has information or attributes regarding the current user. The user is then identified with the given JWT. This is called authentication. Post logging in successfully, different users have different levels of access. While some may access everything, access for others might be restricted to only some resources. The level of access is authorization. 13. How to generate a class in Angular 7 using CLI?
This will generate a class named Dummy. 14. Explain what is the difference between Angular and Backbone.js?The following are the differences between Angular and Backbone.js
15. What are templates in Angular?Written in HTML, templates in Angular contain Angular-specific attributes and elements. Combined with information coming from the controller and model, templates are then further rendered to cater to the user with the dynamic view. 16. Explain the difference between an Annotation and a Decorator in Angular.In Angular, annotations are used for creating an annotation array. They are the only metadata set of the class using the Reflect Metadata library. Decorators in Angular are design patterns used for separating decoration or modification of some class without changing the original source code. 17. What are directives in Angular?Directives are one of the core features of Angular. They allow a developer to write new, application-specific HTML syntax. In actuality, directives are functions that are executed by the Angular compiler when the same finds them in the DOM. Directives are of three types:
18. What are the differences between Angular and jQuery?The single biggest difference between Angular and jQuery is that while the former is a JS frontend framework, the latter is a JS library. Despite this, there are some similarities between the two, such as both features DOM manipulation and provide support for animation. Nonetheless, notable differences between Angular and jQuery are:
19. Could you explain the difference between Angular expressions and JavaScript expressions?Although both Angular expressions and JavaScript expressions can contain literals, operators, and variables, there are some notable dissimilarities between the two. Important differences between Angular expressions and JavaScript expressions are enlisted below:
20. What is Angular Material?It is a UI component library. Angular Material helps in creating attractive, consistent, and fully functional web pages as well as web applications. It does so while following modern web design principles, including browser portability and graceful degradation. 21. Why prioritize TypeScript over JavaScript in Angular?TypeScript is a superset of Javascript as it is Javascript and extra features like typecasting for variables, annotations, and variable scope, among other things. It is purely object-oriented programming and offers a compiler that can convert it to Javascript-equivalent code. Advanced Angular Interview Questions22. Define the ng-content Directive.Conventional HTML elements have some content between the tags. For instance:
Now consider the following example of having custom text between angular tags:
However, doing so won’t work the way it worked for HTML elements. In order to make it work just like the HTML example mentioned above, we need to use the ng-content Directive. Moreover, it is helpful in building reusable components. Know more about the ng-content directive. 23. Describe the MVVM architecture.The MVVM architecture removes tight coupling between each component. It has three parts: The architecture allows the children to have reference through observables and not directly to their parents.
The following code demonstrates how to navigate between different routes in an Angular app dubbed “Some Search App”:
An Angular application consists of components and templates that a browser cannot understand. Therefore, every Angular application needs to be compiled before running inside the browser. The Angular compiler takes in the JS code, compiles it, and then produces some JS code. It is known as AOT compilation and happens only once per occasion per user. There are two kinds of compilations that Angular provides:
Advantages of AOT compilation:
26. Explain the concept of scope hierarchy in Angular.Angular organizes the $scope objects into a hierarchy that is typically used by views. This is known as the scope hierarchy in Angular. It has a root scope that can further contain one or several scopes called child scopes. In a scope hierarchy, each view has its own $scope. Hence, the variables set by a view’s view controller will remain hidden to other view controllers. The following is a typical representation of a scope hierarchy:
27. How do Observables differ from Promises?As soon as a promise is made, the execution takes place. However, this is not the case with observables because they are lazy. This means that nothing happens until a subscription is made. While promises handle a single event, observable is a stream that allows the passing of more than one event. A callback is made for each event in an observable. 28. What are the building blocks of Angular?There are essentially 9 building blocks of an Angular application. These are:
Learn Angular Faster With This Bootcamp29. What is Data Binding? In how many ways can it be executed?Data binding is used to connect application data with the DOM (Data Object Model). It happens between the template (HTML) and component (TypeScript). There are 3 ways to achieve data binding:
30. Draw a comparison between the service() and the factory() functions.Used for the business layer of the application, the service() function operates as a constructor function. The function is invoked at runtime using the new keyword. Although the factory() function works in pretty much the same way as the service() function does, the former is more flexible and powerful. In actuality, the factory() function is to design patterns that help in creating objects. 31. Explain the digest cycle in Angular.The process of monitoring the watchlist in order to track changes in the value of the watch variable is termed the digest cycle in Angular. The previous and present versions of the scope model values are compared in each digest cycle. Although the digest cycle process gets triggered implicitly, it is possible to start it manually by using the $apply() function. 32. Explain the various types of filters in AngularJS.In order to format the value of expression so that it can be displayed to the user, AngularJS has filters. It is possible to add these filters to the controllers, directives, services, or templates. AngularJS also provides support for creating custom filters. Organizing data in such a way that it is displayed only when certain criteria are fulfilled is made possible using filters. Filters are added to the expressions using the pipe ‘|’ character. Some AngularJS filters are:
33. What is SPA(Single Page Application)? Contrast SPA technology with traditional web technology. With SPA technology, only a single page - index.HTML - is maintained, although the URL keeps on changing. SPA technology is faster and easier to develop than traditional web technology. In conventional web technology, as soon as a client requests a web page, the server sends the resource. However, when again the client requests for another page, the server responds again with sending the requested resource. The problem with this technology is that it requires a lot of time. 34. What is the code for creating a decorator?We create a decorator called Dummy:
35. What is ViewEncapsulation and how many ways are there to do it in Angular?To put it simply, ViewEncapsulation determines whether the styles defined in a particular component will affect the entire application or not. Angular supports 3 types of ViewEncapsulation:
36. What are Lifecycle hooks in Angular? Explain some life cycle hooks.Angular components enter their lifecycle from the time it is created to the time it is destroyed. Angular hooks provide ways to tap into these phases and trigger changes at specific phases in a lifecycle.
How Do You Prepare for an Angular Interview?To prepare for an Angular interview, you should be aware of the latest standards and practices of various aspects of web development processes. This includes knowing TypeScript, JavaScript, HTML, and the application of these skills. You also want to do research on the particular company you are applying for. This will give you a sense of what they expect, and you can prepare accordingly. Don’t forget that actual coding and building is also very important. You should be ready to demonstrate your knowledge, and that is best practiced through hands-on work. You can look up Angular coding questions to help you practice. ConclusionYou need to be confident while giving the Angular interview. Also, if you’re asked a question you don’t know the answer to, a simple “That’s a good question, I’d have to get back to you on that one,” is better than giving some random non-answer and adding unnecessary details. Candidates that are straightforward and honest are preferred over those pretending to be know-it-alls! Further, don’t disburse your personal details until asked for. The interviewer is more interested in knowing you as a technical person. So, all the very best! Do let us know the Angular questions you faced in the interview that are not covered here so that we can add those here for the benefit of the Angular community. Are these questions also relevant as Angular JS Interview Questions? Yes, these questions are helpful while preparing for the AngularJS interview. Angular is the top programming language and is used by most web developers. If you are looking for more interview questions, you can buy this great course for coming interviews: The Complete Angular Course: Beginner to Advanced. In general programming interviews, another question is also asked so here is a great book with top programming questions and answers: Cracking the Coding Interview: 189 Programming Questions and Solutions. Frequently Asked Questions1. What are basic Angular interview questions?The basic Angular interview questions listed above cover just about all the basic concepts of the framework. These include such things as Angular’s features, and its advantages and disadvantages. Additionally, concepts such as architecture, services, and directives are also fundamental. 2. What is Ng in Angular?Ng stands for next generation, and it relates to built-in directives in Angular. Directives are classes that add behavior to elements. 3. What are pipes in Angular?Pipes are a feature that transforms values in Angular templates. They simply accept a value, perform a function on it, and then produce an output. |