Top Angular Interview Questions You Must Prepare In 2020

Are you aspiring to start your career as an Angular developer? Well, then you are in the right place. To give the best performance in the Angular interview you need prior preparation. We are here to help you out with frequently asked Angular Interview questions and answers. Angular is a powerful web development framework and helps the developers in reaching greater heights in their career. It has gained huge popularity because of its ability to develop single-page applications.

We have grouped here the top Angular interview questions and answers based on the expert’s advice. In any typical Angular interview, the interviewer starts asking with basic questions and based on your answers the interviewer will move to the advanced levels. So, to simplify the learning process let’s start with basic Angular interview questions and later move to the Advanced Angular Interview Questions.

Table of Contents

Frequently Asked Angular Interview Questions: 

1) What is Angular?

Ans:
Angular is an open-source platform for building Desktop and Mobile applications. It is one of the popular Javascript frameworks and managed by Google. Using the Angular platform developers can easily develop web and mobile applications and also help in building cross-platform applications. It creates seamless integration with features like an end to end tooling, declarative templates, dependency injection and much more which all together empowers the development path.

2) Why is Angular Used For?

Ans:
Angular is mainly used for developing compelling Single Page web applications. Angular comes with a set of modules that simplifies the development of Single Page Applications. The other features which make it so popular are built-in streaming, modular CLI, type safety, and a lot more other unique features.

3) What are the benefits of using Angular?

Ans:

Following Are The List of Major Benefits Using the Angular Framework:

  • Two-way data-binding
  • Support Angular and static template
  • MVC pattern architecture
  • Validations are supported
  • Supports RESTful services
  • Allowed Server and client communication
  • Comes with solid features like Animation, Event Handlers, etc.
  • Supports dependency injection

4) What are Angular Expressions?

Ans:
Angular expressions are code snippets that are written inside double braces: {{ }}.
Angular helps the developers in binding application data to an HTML. The syntax for the Angular expression is {{ expression }}.

5) Explain about templates in Angular?

Ans:
Templates in Angular are written in HTML and consist of elements and attributes that are Application-specific. Angular templates are developed with the information that comes from the controller and model and later rendered to give a dynamic view to the user.

6) What do you know about controllers in Angular?

Ans:
Controllers are JavaScript functions that supply logic and data to the HTML user interface. As the name depicts they control the data flow from server to HTML user interface.

7) What are Directories and how many types of Directories are there in Angular?

Ans:

Angular directives are attributes that help you to write new HTML syntax that is suitable for your application. We have 3 types of Angular directories which are:

  • Structural Directives
  • Component Directives
  • Attribute Directives

8) Define Scope in Angular?

Ans:
Scope in Angular is defined as an object that relates to an application model. It acts as an execution context for expressions. Scope mimics the DOM structure of an application when you arrange them in a hierarchical manner. They can also propagate events and watch expressions.

9) What is the main difference between Decorator and Annotation in Angular?

Ans:

Annotations:
In Angular Annotations are metadata of a specific class. Annotations are helpful for creating other annotation arrays.

Decorator:

It is a design pattern used to segregate the modification or decoration of a class without making any changes to the source code.

10) What do you understand by String Interpolation?

Ans:
String Interpolation is a special syntax that displays the component data by using expression within double curly braces {{ }}. It is also called with the other name known as moustache syntax. All the JavaScript expressions are placed in the curly braces and are executed by Angular. Interpolation is nothing but embedded expressions into marked-up text.

11) What is Data Binding in Angular?

Ans:

 

Data binding enables you to define the communication process between the Document Object Model and Component. It streamlines the process to define interactive applications without any need to push and pull data between your template and view and component. We are four different types of data binding in Angular:

  • Property Binding
  • String Binding
  • Event Binding
  • Two-way Data Binding

12) What is the use of filters in Angular?

Ans:
Filters are used in Angular in order to format the value of an expression and thereby enable the view to a user. Angular Filters can be applied to directives, templates services to controllers. Moreover, you can also make custom filters. Filters help you to set criteria to display data. You can add filters to the expressions with the pipe character.

13) What do you understand about providers in Angular?

Ans:
A provider in Angular is an instruction process to the dependency injection that helps with the information to get a value for dependency. It comes with a $get() method which helps in creating a new instance of a service. A provider has multiple methods and uses $provide to register new providers.

14) How many ways can you make communication between the applications using core Angular Functionality?

Ans:

Following Are The Typical Communication Ways Using Core Angular Functionality:

 

  • Using services
  • Using events
  • Assigning models on $rootScope
  • Between Controllers using $childHead, $parent, $nextSibling, etc.
  • Using controllers, or other forms of inheritance.

15)Explain the difference between the $scope and scope?

Ans:
$scope: It is mainly used in Angular to implement the dependency injection (D.I). It is a service provided by $scopeProvider and you can inject this $scope in directives, controllers or other services.
Scope: In Angular, the Scope is employed for directive linking. Sope can be anything like parameter name, etc.

16) What is JQLite?

Ans:
JQlite is a subset of jQuery and comes with all its features. It resides in Angular by default. jQLite allows the Angular to make changes to DOM. It is typically used when the function result is having a little effect.

17) What is AOT (Ahead of Time)?

Ans:
AOT is abbreviated as Ahead-of-Time compiler and is used during the building process to pre-compilation of components and temples. Application of Angular compiled with the AOT takes very less time. Moreover, these applications can be executed immediately and need no client-side compilation. AOT eliminates the need to download Angular compiler.

18) What is Angular Services?

Ans:
Angular services are singleton objects and contain the methods to maintain data of an application for its lifetime. The main objective of a service is to give a structure and share business models, logic, or data. Services work along with other Angular components of an application.

19) Explain the various events in Angular?

Ans:

Following are the various events supposed by Angular:

  • ng-keypress
  • ng-key down
  • ng-dblclick
  • ng-cut
  • ng-copy
  • ng-keyup
  • ng-mouseenter
  • ng-mousedown
  • ng-mousemove
  • ng-mouseleave
  • ng-blur
  • ng-mouseup
  • ng-mouseover
  • ng-mousemove

20) Explain the building blocks of Angular?

Ans:

Following are the 9 building blocks of an angular application:

  • Components
  • Data Binding
  • Dependency Injection (DI)
  • Directives
  • Metadata
  • Modules
  • Routing
  • Template
  • Services

21) What do you understand by the term Angular Material?

Ans:
Angular material helps the developers in designing and developing innovative, highly attractive and full-fledged web applications and web pages.

22) What is the Digest cycle?

Ans:
The Digest cycle is used to monitor the watchlist with an aim to track changes over a period of time. In each digest cycle, previous and present scope model values are analysed and compared.

23) Name the components on which we can create custom components?

Ans:

Following are the components on which we can create custom components:

  • Element directives
  • Attribute
  • Comment
  • CSS

24) What are the various types of filters in Angular?

Ans:

Following are the various filters available in Angular:

  • Date
  • Filter
  • Currency
  • Limit
  • JSON
  • Number
  • Lowercase
  • Uppercase
  • OrderBy

25) Name a few tools to test the Angular Applications?

Ans:

 

Following are the commonly used tools to test the Angular Applications.

  • Karma
  • Sion
  • Browserify
  • Mocha
  • Angular Mocks


Conclusion

Angular is one of the most popular and widely used web and mobile application development frameworks and learning this would give you a promising career. Till now we have covered the frequently asked Angular Interview questions. Mastering these questions will make you confident and help you to give your interview with ease. Hope these top Angular interview questions article have helped you gain knowledge. Happy learning!