AngularJS Interview Questions and Answers

Technology is the future! With different software applications adding mobility to our daily lives, the term ‘developer’ is prevalent among the masses. Today, almost every aspiring student dreams of becoming a developer, with JavaScript as the highlight of their forte! 

AngularJS has been one of the most widely used JavaScript frameworks practiced by a vast number of engineers. Developers that know their ways around development using AngularJS are highly demanded as the development program is essential for an organization’s digital progress. 

Considering their significance and the value they add, recruiters are very keen on finding the right talent onboard. This makes cracking interviews the hard part for developers! 

Are you an Angular JS developer going for an interview? Or, preparing to sit for one? In that case, this article might be of some help to you. Let’s have a look at the top 15 Angular Interview Questions that are generally asked during an interview:

1. What do you understand by the term ‘Angular’?

The term Angular can be defined as an open-source front-end web framework. One of the most popular JavaScript frameworks, Angular is a language that Google maintains. The platform allows users to develop different web-based applications that will enable users to curate cross-platform applications.

2. Can you name some advantages of using Angular?

Listed below are some of the significant advantages of using an Angular framework:

• It supports two-way data-binding
• You can add a custom directive
• It follows MVC pattern architecture
• It supports static template and Angular template
• Client and server communication is facilitated
• Support for dependency injection
• Validations are supported
• Has robust features like Event Handlers, Animation, etc.
• It also supports RESTfull services.

3. Can you explain the term ‘Angular Expression’?

The term ‘Angular expression’ refers to the code snippets. These codes are usually placed around a binding. Example: {{ expression }} that is similar to JavaScript. The primary use of these expressions is to use them around application data to HTML.

This is the syntax used for Angular Expressions: {{ expression }}

4. Mention some necessary steps that should be used to unit test an AngularJS filter?

Here are some basics:

Assert your expectations.
Provide any mocks that the filter relies on.
Inject the module that contains the filter.
Get an instance of the filter using $filter(‘yourFilterName’).

5. Can you tell what the maximum number of concurrent “watches” is? Moreover, how would you keep a check on the number?

The term ‘watches’ allows the users to reduce the consumption of memory and entice the performance as it is an excellent idea that will enable developers to limit the total number of watches that are provided on a page.

The lag is a result of an application failing to continue with a seamless screen refresh rate. To achieve a reliable speed of 60 frames-per-second, the given time to execute a code is 16 milliseconds. The use of the digest cycle and memory use allows it to affect the number of watches that are activated directly.

6. How would you define the term ‘scope’ in Angular?

The term ‘Scope’ in the programming language Angular is an object that means application model. Used as an expression for execution context, scopes are arranged in a hierarchy format, allowing the system to use the DOM structure of a given application.

7. What is the step to share data between different controllers?

To begin the process, you need to create an AngularJS service, allowing the developer to hold data and infuse it around the controllers.

Using service is one of the most prominent and fastest, cleanest ways to run a test. Now, there are also some other controllers like:

– The use of events
– The use of nextSibling, $parent, controllers, etc. to allow direct access to controllers
– Introducing your system to $rootScope, allowing users to include data

The suggested methods are correct and can be used to test efficiently.

8. Suppose you want to migrate from Angular 1.4 to Angular 1.5. Can you tell me the main thing that needs refactoring?

You can quickly adapt from Angular 1.4 to 1.5 by using .directive to .component, allowing users to adjust to the components of Angular 1.5.

9. Can you What is the difference between one-way binding and two-way binding?

One-way binding: It means setting up a scope variable around HTML, allowing developers to set the primary value as its model that it is assigned to.

Two-way binding: This term defines how different scope variable changes and how new values are used, every time the models are assigned to a different value.

10. Can you tell me what makes angular.copy() a powerful method?

Yes, it allows developers to create a deep copy of the suggested variable.

11. Can you explain what data binding is?

In AngularJS, the term binding refers to defining the communication between components and DOM. One of the most influential and important features. The act simplifies the overall process of defining interactive applications. In Angular, developers can use four forms of critical data:

• String Interpolation
• Event Binding
• Property Binding
• Two-Way Data Binding

12. Can you tell me where I should implement the DOM manipulation when I’m using AngularJS?

In such a situation, the DOM Manipulations should not exist around the controllers, services or present anywhere close to the directives.

13. Would it be a bad or good practice if you use AngularJS paired to jQuery?

No, it is not a good practice to go with.

14. How can I do Language Internationalization over AnglarJS?

The answer to this is simple, you need to replace both string literals with tokens.

15. What is Isolate Scope?

The term Isolate Scope refers to a scope that does not inherit anything from the traditional program and exists on its own.

Conclusion

Listed above were some of the most commonly asked yet important Angular Interview Questions that an AngualrJS developer will come across in interviews. You can go through them, prepare and you are good to go.

We hope that you crack the interview with ease and confidence; all the best!