Top Angular 2 Interview Questions and Answers - Essential Guide for Job Seekers

Lazy loading allows developers to load different code pieces on demand. For instance, if you have a retail application that has different departments like garments, groceries, electronics, etc. If you load all the sections, in the beginning, your application will be slow. This is when you need lazy loading. It helps the application load faster because it loads only parts that the user wants to see.

This interview questions on angular 2 are always a level up and thus a little tough to crack.

The simplest way is to put the variables in a file and export them. In order to use global variables, you can use an import statement.

'use strict';

export const name='bestinterviewquestion.com';

After that, we can export this file where we want to use these global variables value.
import * as myGlobalsFile from './globalfile';

Advantages of Angular 2 over Angular are given below-

• Simpler to Learn
• Simpler Dependency Injection
• It’s is a platform not only a language:
• Improved Speed and Performance: No $Scope in Angular 2, AOT
• Modular, cross-platform
• Flexible Routing with Lazy Loading Features
• Benefits of ES6 and Typescript.

In Angular apps, hooks are functions that are called on particular stages of a component’s life. Hooks are essential if your app is based on the component architecture. Example for hooks is $onInit, $onChanges, etc. which are properties pre-defined by Angular and can be exposed on component controllers.

Here are the steps:

• Import injectable member
• Add @Injectable Decorator
• Export Service class

Here is the syntax:

import { Injectable } from '@angular/core';
   @Injectable()
   export class MyCustomService {
}

It is a command-line interface which is used to build angular apps. We can construct & start a project very quickly with the help of CLI.

You can download CLI from its official website https://cli.angular.io

The command for install Angular CLI

npm install –g angular-cli

The AOT compilation converts Angular HTML and TypeScript codes into JavaScript code at some stage in the construct section earlier than the browser can down load and run the code.

Here are benefits of compiling with AOT:

• Lesser asynchronous requests
• Smaller download size of Angular framework
• Detects errors easily
• Fast rendering
• Improved security

Advantages-

• Fast download
• Quicker rendering
• Reduces Http Requests
• Catches errors during the build phase

Disadvantages-

• Only works with HTML and CSS Not other file types.
• Must maintain bootstrap file AOT version
• Must clean-up before compiling.