9 Top Angular Interview Questions and Answers (2023)

Are you looking for an Angular developer? In that case, you need the right Angular interview questions. And today, you get 9 questions to ask your candidates so that you can identify the best fit for the job. Read on!

Angular interviews 

Angular is an open-source web application framework that’s based on TypeScript and developed by Google, as well as a community of individuals and corporations. It’s a complete rewrite from the team that built AngularJS. 

This framework is used as part of the MEAN stack, which consists of MongoDB database, Express.js web application server framework, Angular/AngularJS, and Node.js.

To hire Angular developers, you need the right Angular interview questions. We’ve included our top picks here below to help you interview developers. 

Beginner Angular interview questions

How do you interview Angular junior developers? These questions are a great place to start. With the help of them, you get a better understanding of how well your candidate knows Angular.

1. What is Angular? 

Answer: 

A simple question that can be answered in many different ways. However, it does show if your candidate has a solid understanding of Angular as a framework. 

Angular is a development platform that’s built on TypeScript. Angular includes a component-based framework to build scalable web applications. It also comes with a collection of well-integrated libraries with several features and a suite of developer tools to help you develop, build, test, and update your code. 

The framework is flexible and with it, you can scale your single-developer to enterprise-level projects. Angular makes it easy to update projects and the ecosystem includes over 1.7 million creators and developers. 

2. What is the difference between Angular and AngularJS? 

Answer: 

From the beginning, Google intended Angular to be a rewrite of AngularJS. AngularJS is essentially “version 1” and Angular “version 2.”

The differences between Angular and AngularJS are: 

• Angular uses a different expression syntax (“ [ ] “ for property binding and “ ( ) “ for event binding).
• AngularJS has a Model-View-Controller architecture, which is replaced by Components in Angular. 
• AngularJS uses JavaScript. Angular uses TypeScript, a superset of JavaScript. This helps Angular provide better performance while developing larger applications. 
• Angular is supported by all popular mobile browsers, whereas AngularJS doesn’t have mobile support. 
• AngularJS makes it difficult to manage large applications. With Angular, this is easier. 

3. Why was Angular developed? 

Answer:

Before, developers used VanillaJS and jQuery to develop dynamic websites. However, the code of bigger websites quickly became difficult to manage. That’s why client-side frameworks, like Angular, were developed. They help developers handle the separation of concerns and divide code into smaller bits of information, something that wasn’t possible earlier. 

4. What are the benefits of Angular?

Answer:

This question helps you understand how well your candidate understands the reasons why Angular is used. 

Angular has several benefits. 

• First, it supports the “Model-View-Controller” (MVC) architecture. It helps with the separation of concerns by letting you isolate the application logic from the UI layer. 
• Thanks to its architecture, Angular can be used to locate code that requires changes. 
• “Angular Injector” supports services and dependency injection. 
• Angular has modules, which help developers. 
• By using TypeScript, Angular eliminates common programming errors, which results in better code. 
• Angular can be used for comprehensive documentation. 

Advanced Angular interview questions

What are questions you can ask senior Angular developers? Here are our top picks. 

5. What are the building blocks of Angular? 

Answer:

An Angular application has nine building blocks. There are: 

Components

Each Angular application has at least one component, known as the root component, which is bootstrapped inside the root module (main module). Every component controls one or more views and every view is a specific section of the screen. Components contain application logic defined inside a class, which is responsible for interacting with the view via APIs of properties and methods. 

Dependency Injection (DI)

DI provides required dependencies, services, to new components. The constructor parameter of a component tells Angular about the services that a component requires. Thanks to a DI, fully-formed dependencies can be supplied by a new instance of a class. 

Data binding

Data binding is the process that lets parts of a template coordinate with parts of a component. The binding markup is added to the template HTML to let Angular know how to connect templates and components. 

Metadata

Metadata helps Angular process a class. 

Modules

Or NgModules. They are an organized block of code with specific capabilities and a workflow. There’s at least one module in every Angular application (root module). 

Directives

Angular components are basically directives with a template. They help instruct Angular on how to transform the DOM when rendering a template. 

Routing

An Angular router interprets a browser URL as an instruction to navigate to a client-generated view. This router tells Angular to navigate to the application view when a user clicks on it through the links it’s bound to. 

Services

A service is anything from a value and function to a feature. It’s a class with a well-defined purpose. 

Template 

Every component has a template, which is a form of HTML tags that informs Angular how the component will be rendered. 

6. Explain bootstrapping.

Answer:

Angular manual and automatic bootstrapping let you start the Angular application.

Manual bootstrapping gives more control in terms of initializing the app. It’s useful when you want to perform other tasks and operations before Angular compiles the page.

Automatic bootstrapping helps you add an ng-app directive to the application’s root. Angular then loads the associated module when it finds the ng-app directive and compiles the DOM. 

7. Which types of components can custom directives be created on? 

Answer:

Angular supports the following directives:

• Element directives - This directive activates when a matching element is encountered. 
• Attribute - The directive activates when a matching attribute is encountered.
• Comment - The directive activates when a matching comment is encountered. 
• CSS - Directive activates when a matching CSS style is encountered. 

8. What is “dirty checking” in Angular? 

Answer:

“Dirty checking” is the digest process in Angular. It scans the scope for changes and compares the new scope model values with previous values. As all watched variables are contained in a single loop, changes and updates in variables lead to assigning the rest of the watched variables in the DOM. Watched variables are in a single loop, value changes of variables force the reassignment of values of other watched variables in the DOM. 

9. How do you set, get, and clear cookies in Angular? 

Answer:

You will need to include a module called ngCookies angular-cookies.js to use them in Angular. 

Cookies in a key-value format are set by using the ‘put’ method. 

cookie.set('nameOfCookie',"cookieValue");

To get or retrieve cookies, use the ‘get’ method. 

cookie.get(‘nameOfCookie’);

And to clear cookies, use the ‘remove’ method.

cookie.delete(‘nameOfCookie’);

Identify the best Angular developers

There you have it! Now you know what Angular interview questions to ask at your next interview. 

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