Angular 8 Interview Questions and Answers

Ng-hide command is used to hide HTML elements if an expression is true.

Here's an example:

<div ng-app="DemoApp" ng-controller="DemoController">
   <input type="button" value="Hide Angular" ng-click="ShowHide()"/>
   <div ng-hide="IsVisible">Angular 8</div>
</div>
<script type="text/javascript">
   var app = angular.module('DemoApp',[]);
   app.controller('DemoController',function($scope){
   $scope.IsVisible = false;
   $scope.ShowHide = function(){
     $scope.IsVisible = $scope.IsVisible = true;
   }
});
</script>

Now in the above, when the Hide Angular button is not clicked(the expression is set to false)

Angular uses TypeScript because:

• It has a wide range of tools
• It’s a superset of Angular
• It makes abstractions explicit
• It makes the code easier to read and understand.
• It takes most of the usefulness within a language and brings it into a JS environment without forcing you out.

Here are the top new features of Angular 9

• An undecorated class migration schematic added to the core.
• Numeric Values are accepted in the formControlName.
• Selector-less directives have now been allowed as base classes in View Engine in the compiler.
• Conversion of ngtsc diagnostics to ts.Diagnostics is possible

Angular 8 uses observables which are implemented using RxJS libraries to push code. The main job of RxJS is to work with asynchronous events.

NgUpgrade in Angular 8 is a library which is used to integrate both Angular and AngularJS components in an application and also help in bridging the dependency injection systems in both Angular & AngularJS.

The ng lint command is used to run static code analysis within an Angular application.

Steps for the Installation of Angular 8 environmental setup

Step 1

Before installing Angular IDE using Angular CLI tool, make sure that Node.js has already installed in your system.

• 1. If Node.js is not installed in your system install it using the following steps.
  • The basic requirement of Angular 8 is Node.js version 110.9.0 or later.
  • Download it using https://nodejs.org/en/
  • Install it on your system
  • Open node.js command prompt
  • Check the version run command, node-v in the console window

Step 2

In order to install Angular CLI, use the following commands 2) npm install –g @angular/cli or npm install –g @angular/cli@latest

Step 3

To check the node and angular CLI version, run command ng –version on the console terminal

Angular 8 introduced a number of new and unique options to runGuardsAndResolvers. In general, runGuardsAndResolvers is an option which is used for the Angular router configuration in order to control the resolvers and guards. The first option available in runGuardsAndResolvers is pathParamsChange. Through, this option router will re-run the guards and resolvers. Whenever you want to control over the resolvers and guards, use runGuardsAndResolvers option in Angular 8.