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

In Angular, lifecycle hooks are functions which will be called at specific points of a component lifecycle in Angular applications.

They are highly crucial for a component architecture based application.

Angular 2 is the upgraded and evolved version of AngularJS, a JavaScript framework that was invented by Google. Angular 2 is used for building single-page web or mobile applications.

Components are essential elements of Angular 2 apps, and an application can have a number of components. In Angular 2, components perform all the tasks that were done by scopes, controllers and directives, such as creating or adding Data, logic, and custom elements.

In Angular 2 a component consists of the following:

• Template
• Class
• Metadata

When a page containing Angular based application loads, these below-mentioned scenarios will be completed.

• The browser will load the HTML document and evaluate it.
• The file for AngularJS JavaScript will be loaded and the Angular global object will be created.
• Finally, the JavaScript that registers controller function will be executed.

In Angular 2, deep linking is a process of the URL that will take to users to a specific page or content directly without crossing the application from the homepage. The deep linking process helps with website or application indexing so that search engines can easily crawl these links.

As services are reusable singleton objects in AngularJS which is used to organize and share codes across the application, they can be injected into filters, controllers, and directives. Angular 2 offers three ways to create a service; factory, service, and provider.

The factory function allows developers to include some logic before creating the object and returns the created object. The syntax for factory function is as follows.

app.factory('serviceName',function(){ return serviceObj;})

Routing is what lets in you to create Single Page Applications. AngularJS routes allow you to create distinct URLs for one of a kind content material in your application. It helps in redirecting users to exceptional pages based totally on the alternative they pick out on the main page. AngularJS routes enable one to show more than one content depending on which route is chosen. A route is unique in the URL after the # sign.

Using angular routing you can navigate from one view or page to another while performing your tasks. You can configure a URL to redirect to the next URL. This feature can be handled to address the "404 Not Found" problem. Using location services in Angular routing you can go back and forward through the history of pages.

Syntax : We can use {path: '/OUR_PATH', redirectTo: ['redirectPathName']}

It is an open source tool for running and checking if the pre-defined coding guidelines were followed or not. It does static code analysis for typescript and angular projects.

It runs on top of tslint and coding conventions are defined in tslint.json file. Editors such as Visual Studio Code support codelyzer by doing basic settings.