Top Angular 2 Interview Questions and Answers - Essential Guide for Job Seekers
To survive in the modern industry and to earn a very good salary, learning only JavaScript programming language is not sufficient, you must move on to learning JavaScript Frameworks also i.e., Angular. It doesn’t matter if you are thinking to start your career in software development or are already a software developer, you will always find Angular 2 Interview Questions useful. This is an open-source component-based UI framework that is written in TypeScript and is mainly used in building web, mobile, and desktop applications in HTML and JavaScript. Angular is an evolved and upgraded version of Angular JS and is invented by Google. For writing codes, Angular provides many language choices like Typescript, Dart, ES5, ES6. It supports both data and property blinding which allows a user to control DOM i.e., Data Object Model by binding class and HTML properties.
| Quick Facts About Angular 2 | |
|---|---|
| What is the latest version of Angular? | Angular 14 released on 2nd June 2022 |
| When did angular 6 release? | 14th September 2016 |
| Who is the developer of Angular 2? | |
| What language does Angular use? | TypeScript |
| License | MIT License |
| Official website | https://angular.io |
Frequently Asked Angular 2 Interview Questions for Developers
Modal footer is basically used when the template is fully loaded. User needs to write the code inside the ngAfterViewInit then users will not get the footer element. Thus, footer modal is life cycle event which is used to check whether the Dom is fully loaded or not.
The injectable decorator in Angular 2 allows the functionality of the creation of a service to be injected and used in AngularJS modules by defining it as a provider in the Component Decorator.
Following is a syntax to successfully create a service using the Injectable() decorator
import { Injectable } from '@angular/core';
import { Item } from './item';
import { ITEMS } from './mock-items';
@Injectable()
export class ItemService {
selectedItems: Item[] = [];
getItems(): Item[] {
return ITEMS;
}
getSelectedItems(): Item[] {
return this.selectedItems;
}
addItem(id:number): void {
let item = ITEMS.find(ob => ob.id === id);
if (this.selectedItems.indexOf(item) < 0) {
this.selectedItems.push(item);
}
}
removeItem(id:number): void {
let item = this.selectedItems.find(ob => ob.id === id);
let itemIndex = this.selectedItems.indexOf(item);
this.selectedItems.splice(itemIndex, 1);
}
Property binding
When you have to pass the value from a parent component in ANgular to a child component, we have to use the property binding meaning that by doing so we are sending the value using the attribute on a component and thereby get the parent using the @Input annotation for the example of property binding like the below example: <my-child [myProp]="prop" />
Event Binding
Caching of Child’s Event/Method using the parent component.
This is used when we have to fire some event on click or maybe something else from the child component while passing it to the Parent.
Here’s an example:
<my-child [myProp]="prop" (onPropChange)="onPropChange($event)"</strong> /> Here, we have user onPropChange as event binding to catch and fire an event using EventEmitter.
In Angular, the package.json file lets you keep a track of dependencies within a project. By using the reference of these packages in the dependency section, it enables you to use a module bundler such as webpack, browserify, etc. The package.json also helps you to keep your project linked to the specific versions of each package if the new version introduces any changes.
In Angular, the main.ts is the entry point of the application, which runs first when you render a page in Angular. It compiles the application with JIT and bootstraps the Angular application. In Angular 2, you can bootstrap multiple environments to import a module specific to the environment during which angular looks for a specific module to run first.
- Angular Interviews are not just about learning Java Concepts but one of the toughest questions is to know about software and system designs.
- Practice is the key factor to crack any type of interview. Angular interviews are no exception too.
- You should know about basics such as TypeScript, Services, Metadata, Components, etc.
- If you know about the answer but you are taking too much time to explain it, then that land you nowhere. So yes, Time Yourself i.e. answer your question within a time limit.
- Teach a concept to your friend or anyone which you have learned. By this, you will know if you learn that concept.
- Honesty is the best policy. If you don’t know the answer just admit it without wasting the interviewer and your time.