Top 10 AngularJS Interview Questions and Answers

Most asking Top 10 AngularJS Interview Questions and Answers. Please read below questions and answers.

Q#1. What is AngularJS?

A#1. AngularJS is a framework to build large scale and high performance application.

AngularJS is a very powerful JavaScript Framework.
It is provides developer to write a client side application in MVC method.
Open source and free. And used by many developers and tested.

Q#2. What are the controllers in AngularJS?

A#2. Controllers are JavaScript functions. They decide which view is to be updated to show the updated model based data.

Q#3. What are filters in AngularJS?

A#3. Filters select a subset of items from an array and return a new array. Filters are used to show filtered items from a list of items based on defined criteria.

Q#4. What is routing in AngularJS?

A#4. ngRoute module you can use to navigate the pages in AngularJs.

Example from w3school

<body ng-app="myApp">

<p><a href="#/!">Main</a></p>

<a href="#!red">Red</a>
<a href="#!green">Green</a>
<a href="#!blue">Blue</a>

<div ng-view></div>

<script>
var app = angular.module("myApp", ["ngRoute"]);
app.config(function($routeProvider) {
    $routeProvider
    .when("/", {
        templateUrl : "main.htm"
    })
    .when("/red", {
        templateUrl : "red.htm"
    })
    .when("/green", {
        templateUrl : "green.htm"
    })
    .when("/blue", {
        templateUrl : "blue.htm"
    });
});
</script>
</body>

<a href="#!green">Green</a>

var app = angular.module("myApp", ["ngRoute"]);

app.config(function($routeProvider) {

$routeProvider

.when("/", {

templateUrl : "main.htm"

})

.when("/red", {

templateUrl : "red.htm"

})

.when("/green", {

templateUrl : "green.htm"

})

.when("/blue", {

templateUrl : "blue.htm"

});

</script>

</body>

Q#5. What are the advantage of AngularJS?

A#5. AngularJS are as follows

AngularJS provides capability to create Single Page Application.
AngularJS code is unit testable.
AngularJS provides reusable components.
In AngularJS, views are pure html pages, and controllers written in JavaScript do the business processing.
With AngularJS, developer writes less code and gets more functionality.

Q#6. What are the disadvantages of AngularJS?

A#6. Disadvantages are as follows.

Not Secure − Being JavaScript only framework, application written in AngularJS are not safe. Server side authentication and authorization is must to keep an application secure.
Not degradable − In browser is javascript disabled then users just able to see basic page.

Q#7. Explain ng-app and ng-model directive.

A#7. ng-app directive links an AngularJS application to HTML and also indicate the start of the application. ng-model directive binds the values of AngularJS application data to HTML input controls. It creates a model variable which can be used with the html page and within the container control( like div) having ng-app directive.

Q#8. Explain ng-init directive.

A#8. ng-init directive initialize the AngularJS application data. It is used to put values to the variables which is used in Application.

Q#9. How to make an ajax call using Angular JS?

A#9. AngularJS provides $https: control which works as a service to make ajax call to read data from the server. The server makes a database call to get the desired records. Using this we have create CRUD application using php you can use this link.

function studentController($scope,$https:) {
   var url = "data.txt";
   $https:.get(url).success( function(response) {
      $scope.students = response; 
   });
}

function studentController($scope,$https:) {

var url = "data.txt";

$https:.get(url).success( function(response) {

$scope.students = response;

});

}

Q#10. Is AngularJS extensible?

A#10. Yes! In AngularJS we can create custom directive to extend AngularJS existing functionalities. Custom dir