AngularJS Introduction

⇒ AngularJS is a JavaScript Framework. It can be added to an HTML page with a <script> tag.

⇒ AngularJS extends HTML attributes with Directives and binds data to HTML with Expressions.

AngularJS is a JavaScript Framework

⇢ AngularJS is a JavaScript Framework. It is a library written in JavaScript.

⇢ AngularJS is distributed as a JavaScript file, and can be added to a web page with a script tag:

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script>

AngularJS Extends HTML

⇢ AngularJS extends HTML with ng-directives.

⇢ The ng-app directive defines an AngularJS application.

⇢ The ng-model directive binds the value of HTML controls (input, select, textarea) to application data.

⇢ The ng-bind directive binds application data to the HTML view.

AngularJS Example:

<!DOCTYPE html>

<html>

<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.6.9/angular.min.js"></script>

<body>

<div ng-app="">

<p>Name: <input type="text" ng-model="name"></p>

<p ng-bind="name"></p>

</div>

</body>

</html>

Example explained:

⇢ AngularJS starts automatically when the web page has loaded.

⇢ The ng-app directive tells AngularJS that the <div> element is the "owner" of an AngularJS application.

⇢ The ng-model directive binds the value of the input field to the application variable name.

⇢ The ng-bind directive binds the content of the <p> element to the application variable name.

AngularJS Directives

⇢ As you have already seen, AngularJS directives are HTML attributes with an ng prefix.

⇢ The ng-init directive initializes AngularJS application variables.

Example :

<div ng-app="" ng-init="firstName='John'">

<p>The name is <span ng-bind="firstName"></span></p>

</div>

AngularJS Expressions

⇢ AngularJS expressions are written inside double braces: {{ expression }}.

⇢ AngularJS will "output" data exactly where the expression is written:

Example :

<!DOCTYPE html>

<html>

<body>

<p>My first expression: {{ 5 + 5 }}</p>

</div>

</body>

</html>

⇢ AngularJS expressions bind AngularJS data to HTML the same way as the ng-bind directive.

Example :

<!DOCTYPE html>

<html>

<body>

</div>

</body>

</html>

AngularJS Applications

⇢ AngularJS modules define AngularJS applications.

⇢ AngularJS controllers control AngularJS applications.

⇢ The ng-app directive defines the application, the ng-controller directive defines the controller.

Example :

First Name: <input type="text" ng-model="firstName"><br>

Last Name: <input type="text" ng-model="lastName"><br>

<br>

Full Name: {{firstName + " " + lastName}}

</div>

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

app.controller('myController', function($scope) {

$scope.firstName= "Dhaval";

$scope.lastName= "Purohit";

});

</script>

➤ AngularJS Module :

⇢ AngularJS modules define applications:

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

➤ AngularJS Controller :

⇢ AngularJS controllers define applications:

app.controller('myController', function($scope) {

$scope.firstName= "Dhaval";
$scope.lastName= "Purohit";
});

Note: AngularJS expressions bind AngularJS data to HTML the same way as the ng-bind directive.

AngularJS Introduction