AngularJs is a widely used framework across the world for simplifying the process of testing and developing applications. The importance of AngularJS has been increasing all over the globe. The individuals who want to raise their career as an AngularJs developer, have bright career opportunities in the market.

If you are going to attend an AngularJS interview, then it is a must for you to know in-depth about AngularJS, and type of Angular interview questions that are commonly asked in an interview. In this blog, we have listed Top 6 different versions of AngularJS interview questions. Below mentioned versions of AngularJS interview questions and answers are going to be covered here:

AngularJS Interview And Questions

1) What is AngularJs?

Ans: AngularJs is an open-source JavaScript framework which helps to build high scale and extensible web applications. It works with HTML and JavaScript. All the components can be mentioned clearly in the applications using HTML. It is best for single web page applications. It is used in the combination of HTML UI elements with JavaScript objects.

2) What are the key features of AngularJS?

Ans: Following are the key features of AngularJS: It is completely free and open-source, hence used by many developers around the world. AngularJS is a highly extensible JavaScript framework, which creates strong web applications. It helps to enable HTML as a template language AngularJS handles the code for each application written on the web page It enables the developer to create high performable application over the internet.

3) What is meant by Scope?

Ans: Scope means an application model in AngularJs. It acts as an interface between views and application controller. These scopes are arranged in a sequential manner and reflect DOM(Document Object Model).

4) What is Data Binding in AngularJs?

Ans: An automatic co-occurrence of data between view and model components is known as data binding.

5) What is mean by services in AngularJs?

Ans: Services are the singleton functions and objects in Angular Js which are used to carry out specific tasks. These are logical and the functions of services can be called controllers, filters and directives.

6) What are the types of data binding in AngularJS?

Ans: There are two types of data binding, they are

  1. One way Binding - In one way binding if the data model changes there will be no changes in a dynamic view of the function.
  2. Two-way Binding - In two-way binding, if data model changes then the whole dynamic view changes with respect to the changes made in the model.
7) What are the directives and mention some of the important types of directives?

Ans: Directives are the extended HTML attributes with the prefix “ng”.

ng-bind
ng-bind template
ng-non bindable
ng-bind HTML
ng-model
8) What is Angular expression? What are the differences between angular and java expressions?

Ans: The angular expression is a code snippet used in data binding. They are usually defined as {{ expression}}. Differences between Angular expressions and JavaScript expressions: Control Statements like conditions, loops, and exceptions are not used in angular expressions. We can use filters to format the data before display. In angular expression, forgiving is to define null and undefined, whereas, in JavaScript, the properties generate reference error and type error These expressions are evolved in the place of scope objects, wherein JavaScript expressions are evolved in the place of a global window.

9) Where can we implement DOM in AngularJS?

Ans: A DOM manipulation is done in only the directives, moreover, it cannot be done in the services, controller and anywhere else.

10) How to allow a scope to only one way binding?

Ans: TO allow a scope to one way binding in front of the scope, we have to define “::”.

Checkout AngularJS Tutorial

11) What is the difference between scope and $scope?

Ans: The scope is the interface which helps to link between views and controller. $scope is used to define the dependency injection.

12) What is dependency injection in AngularJS?

Ans: IN Angular JS, the dependency injection is a software mechanism in which the components are given their dependencies instead of hard codes. It helps in maintaining a component as reusable and extensible. It provides key components like value, service, constant, provider and factory in which the dependencies are injected from one to other.

13) How the prefixes $ and $$ are used in AngularJS?

Ans: “$” prefix is used to define the key components of variable like parameters, method, variable and property. $$ prefix is used to define a variable as private and used to restrict the code collision with other codes.

14) What are the Routes in AngularJS?

Ans: Routes in AngularJS helps to create different URLs for different contents in the applications. This enables the user to bookmark a specified content which he needs. This bookmarked URL is called Route.

15) What is mean by value?

Ans: Value refers to a simple object, it may be a number, character, and string. The value should always belong to a model and these are injected into controllers, factories and services. Adding value to the controller is possible by assigning parameter with the same name as the value.

16) How to initialize a select box om on page load?

Ans: By using ng-init, we can initialize a select box on the on page load.

< div ng-controller ="dashboard/apps/account" ng-switch
on="! ! account" ng-init="rundata()">
17) What is meant by string interpolation?

Ans: At the time of compiling process, the compiler in the angular js matches attributes and views with the help of interpolation, to check embedded expressions. By the digest cycle, all these embedded expressions are recovered and stored as watches.

18) What is linking functions and types of linking functions?

Ans: A linking function links the directives with the scope to produce a view. To register and to update DOM handlers, the linking functions are very important. There are two types of linking functions, they are:

  • Pre-linking functions: This function is executed before the process of child elements linking. Here we can’t transform the DOM.
  • Post-linking functions: This function is executed after the linking process of child elements. In these functions, the transformation of DOM is done safely.
19) What are the controllers in AngularJS?

Subscribe to our youtube channel to get new updates..!

Ans: The controller is a Javascript function which is specified to a particular scope. These are the primary components of Javascript frameworks, which help carry out functions to operate on data and views.

20) Explain the AngularJs boot process?

Ans: When a page has loaded in the browser, the following process takes place:

    • An HTML document of the page is loaded and evaluated by the web browser. A Javascript file is loaded and the global object is created. Later controller functions are executed, which are registered by Javascript
    • Here Javascript scans views and apps through HTML, once the view is scanned, then it is connected with the controller function.
    • Then AngularJs shows the controller functions with views and data handled by the controller. Finally, the page gets ready.
21) What is the difference between AngularJS and backbone.js?

Ans: In AngularJs, all the functions are done on the third-party libraries, it enables functions to carry out individuals which required to develop the HTML applications, wherein backbone.js, all the functions are done in own library.

22) Explain about Routing?

Ans: Routing is a process of merging views. Basically, in this, the controller decides which view should be merged based on the logical need.

23) What are the disadvantages of  Angular Js?

Ans:

  • Security- As Angular JS is an only script framework,  the application done on JavaScript are not secure. A server-side authorization and authentication are key components for every web application.
  • Extensible- When an application developer removes the JavaScript then the user enables only the pageview.
24) What is Model View Controller?

Ans: A Model View Controller is a pattern of designing web applications. In this pattern, there are three types of components:

  • Model: In this level, the data of an application is maintained.
  • View: In this level, all the portions of data is secured.
  • Controller: in this, by software code, the data interacts between view and model.
25) What are the differences between the factory service methods in AngularJs?

Ans: In a factory method, first a factory of objects are defined and then methods are implied to those factories, whereas in the service method, the services are created to define a specific task.

Angular 6 Certification

26) What is $rootscope?

Ans: The scope is a special data model in JavaScript where there is an interaction between views and controllers. In controllers, the data is accessed with the $rootscope. This is the root of all the scopes variables.

27) What is the ng-app directive?

Ans: This ng-app directive helps to include and define the JavaScript application to HTML document. This is a basic level at the start of the application.

28) Explain what is ng-bind directive?

Ans: This directive helps to bind the JavaScript application data to the HTML tags. It also helps to develop the model of data obtained by the model directive to enable input to the user in HTML tags.

29) Explain about ng-model directive?

Ans: In angular js, the ng-model is used to bind the objects of JavaScript application data to the HTML controls. This directive creates a model variable that can be used for the HTML page.

30) Explain what is ng-controller directives?

Ans: ng-controller in angular js helps to decide what type of controllers should be used in the views.

Controllers are the key components in the application for data flow. A controller is an object which includes properties, attributes and functions. Every collector collects $scope which is an application model.

Angular 2 interview questions and answers

31) What is Angular 2?

Ans: Angular 2 is a popular JavaScript framework used for the development of web applications and mobile systems. It is also used in mobile platform development called IONIC, not only for web applications. This framework enables extensible and testable applications.

32) What are the key components in Angular 2?

Ans: Components in Angular 2 are:

  • Modules: An application is broken down into several pieces of code. Each piece is called a module. These modules are created to perform certain specific jobs.
  • Components: Components are used to build a module.
  • Meta Data: It is used to add extra data to the JavaScript class.
  • Templates:  It is used to specify the views of applications in JavaScript
  • Service: These are used to create components.
33) What are the directives in Angular2?

Ans: A directive is an element which is used to customize HTML code. The important directives in Angular 2 are:

  • ngIF-  If it is true then the elements are added to the HTML code, either elements are not added to the code.
  • ngFOR- It is used to get a temporary variable from the variable list.
34) How to handle errors in Angular 2?

Ans: Errors handling feature is available in Angular2 applications. The errors occurred can be handled by React JS catch library and also by using the catch function.

35) List out the browsers supports Angular2?

Ans: The modern browsers which support Angular2 are:

  1. Google Chrome
  2. Edge
  3. Safari
  4. Firefox
  5. IOS 7.1
  6. IE Mobile
  7. Android 4.1
36) How Angular 2 is better from Angular 1?

Ans: Angular 2 is a rewrite version of Angular 1. It is not an updated version to angular1. Angular 2 is an extensible version when compared to the angular 1. We have listed some features which are different in Angular 2 from Angular 1.

Angular 2 Angular 1
It is a mobile development framework It is not suited for mobile development
In Angular 2 there are more language options and we can write code in ES6, ES5, Dart and Typewriter. In Angular 1 there are no more language options. We can write only by using ES6, ES5 and Dart.
Angular 2 is an extensible framework and it is completely a component-based. Angular 2 is an extensible framework and it is completely a component-based.

It is a controller-based framework

37) How to convert a string into currency?

Ans: To convert a string input into a currency type we use currency filter in Angular 2.

Here is an example of adding a currency filter by using pipe character to the expression

<div>
The currency of this expression is{{ new value/  currency}}
<div>
38) Explain about hidden property in Angular 2?

Ans: Hidden property is one of the special case properties in angular 2. It is used to bind elements from one property to another property. It can set the display property to none.

39) What is a template?

Ans: In angular 2 templates are used to determine the views of the applications.

40) Is there any chance to port Angular 1 code to Angular 2?

Ans: There is no such chance of porting the code from angular 1 to angular 2. Till there is no to port code. As they are different frameworks, they require some approaches.

Angular 4 Interview Questions and answers

41) What is mean by components decorators in Angular 4?

Ans: Decorators are the functions which help to modify classes of Javascript. These decorators tell JavaScript classes how to work on metadata. Angular 4 has many decorators for the extensible performance of the application.

Components of the Angular 4 are selectors, styles, providers, templates, and directives. These components will handle HTML code.

42)  What is the isolated unit test in Angular 4?

Ans: The process of conducting tests on the class or component of the angular in an isolated way, rather than creating dependency in between the components is called isolated unit test. In isolated testing, every component and unit is tested under isolation.

43) What are pure functions?

Ans: Pure functions do not change the assigned value and produce the exact output, after assigning the same value for multiple times.

44) What is mean by Transpiling?

Ans: Transpiling is a process of converting the JavaScript(JS) into trance script.

45) What is mean by compilation in Angular 4? What are the types of compilation in Angular4?

Ans: An Angular 4 the compiler compiles the functions and views of the application.

  • Time compilation
  • Ahead of time compilation

Angular 5 interview questions and answers

46) What are the new features of Angular 5? done

Ans: Angular 5 came with certain new features to help the developers in handling smooth coding. The following features are included in the new version of Angular 5, they are:

  • Typescript version 2.4 ahead of Time(AOT)  feature as a default.
  • Fetching Utility and Metadata Handling
  • RxJS 5.5 
  • Pipeable operators
  • Advanced Hybrid upgrade applications
  • Activation start and Activation end in Router
47) What is Transpiling?

Ans: The process of changing typescript into JavaScript with the help of Traceur is known as Transpiling. Even though Angular applications are written in the typescript the code, but the code is transpired internally in the Javascript.

48) What is the use with router.navigate? done

Ans: To route, the components in Angular the router.navigate is used.

Syntax - this.router.navigate([‘/ comp_name’]);
49) What is meant by component?

Ans: An Angular web page is a collection of components. A component is considered as a block which is written in typescript on HTML

50) What is the proper sequence of life cycle hooks in Angular 5?

Ans: Life cycle hooks in Angular 5 helps to execute various activities in the web applications in a sequence. The sequence of hooks is ngOnChanges, ngOnInit, ngDocheck, ngOnDestroy, ngAfterContentInit, ngAfterContentChecked, ngAfterContentChecked and ngAfterViewChecked.

Angular 6 interview questions and answers

51) What is the difference between constructor and ngonint in Angular 6?

Ans:

    • Constructor- It is a default declaration for every object and class, and it is called for every time when a class is initializing It helps in initializing the subclasses and variables of every class.
    • Ngonint- It helps ensure that all the required components are obtained.

Angular 6 training

52) Why do we prefer Angular 6 even angular 5 is efficient?

Ans: Angular 6 is an upgrade version of Angular 5, with some variations in-built.

Here is a list of features in Angular 6:

  • Elements of angular
  • New Engine for Rendering called Ivy
  • RXJS6
  • Animation
  • element Ref
  • I18n
53) What is mean by ngzone?

Ans: The Ngzone is a wrapper for the  JavaScript files and denoted by Zone.js. These are the key libraries in which the tracking of asynchronous functions. It helps in creating the context for the functions.

54) How to identify the specific change router?

Ans: Angular 6 has a feature called Rx event, which is used to determine exact route change.

Angular 8 interview questions and Answers

55) What is new in Angular 8?

Ans: Angular 8 an extensible, faster and easier version to use when compared to other versions. It is easy to handle.

56) what are the features in Angular 8?

Ans:

    • AngularJs improvements in migration
    • Differential loading by default
    • New Deprecation Guide
    • Web Worker Support 
    • Builder CLI and APIs
    • Ivy
    • Bazel
    • Workspace APIs and Angular CLI

Checkout Angular 8 Tutorial