AngularJS hello world example

AngularJs is an open-source web application framework mainly maintained by Google . It aims to simplify both the development and the testing of such applications by providing a framework for client-side model–view–controller (MVC) and model–view–viewmodel (MVVM) architectures,  It helps you to solve major issues with single web page applications. You need to write very less code to achieve complex functionalities.

AngularJS tutorial:

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In this post , we will see how to create angular js example.  I will try to create example as simple as possible.
We need to include angular .js in our pages. This can be done in two ways.
  • go to https://angularjs.org/ and click on download Angular js 1 and copy CDN link
  • You can directly download it from above link and put .js file your folder.

Example :

Copy below text , open notepad , paste it and save it as angularJSExample.html and open it in the browser.

<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Angular js</title>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.5.0/angular.min.js"></script>

</head>
<body>
<div ng-app>
 
 10+40 ={{ 10 + 40 }}
 </br>
 1===2 ? : {{ 1==2 }}
</div>
</body>
</html>


Live demo:

Angular JS example

Explanation:

  • We have included angular js CDN in line number 6
  • If you see closely, we have used ng-app attribute with div element. It is called angular directive (We will learn about this letter). We just need to know that it tells angular about starting point of angular flow. So in this div element , we will have angular js related code.
  • You can understand ng-app as main() method in java
  • {{ }} defines angular expression, so whatever inside it will be evaluated. You can see {{10+40}} becomes 50 here.

What if we do not put ng-app and use angular expression:

  • It won't evaluate the expression as simple as that.
Lets create another div without ng-app and see how it works
Angular js without ng-app

AngularJS did not evaluate expression for second div as it is out of scope for it.

Lets put ng-app at body tag

Angular js ng-app on bidy tag

As you can see, angular js has evaluated expressions for both div tags.

More example:

Lets take another example:
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title>Angular js</title>
<script src="https://ajax.googleapis.com/ajax/libs/angularjs/1.5.0/angular.min.js"></script>

</head>
<body>
<div ng-app>
 Name: <input type="text" ng-model="helloWorld" />
 </br>
  Hello {{ helloWorld}}  !!!
</div>
</body>
</html>

Live demo:

Angular js example

Explanation : 

In this example, we have used textbox, so whatever you write in textbox, get reflected with hello.
  • We have used ng-app same as previous example.
  • If you notice, we have also used ng-model this time. It is also angular directive and it binds state of model and view, so whatever you write in text box, it get reflected in {{helloworld}} . You will be able to understand more about in the coming tutorials.

Written by Arpit:

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