Angular JS Introduction

Angular JS Introduction

Introduction

AngularJS is a very powerful JavaScript Framework. It is used in Single Page Application (SPA) projects. AngularJS extends HTML with new attributes. AngularJS is an open source Model-View-Controller framework which is similar to the 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.

Angular JS is probably one of the most popular modern day web frameworks available today. This framework is used for developing mostly Single Page applications. This framework has been developed by a group of developers from Google itself.

The AngularJS framework works by first reading the HTML page, which has additional custom tag attributes embedded into it. Angular interprets those attributes as directives to bind input or output parts of the page to a model that is represented by standard JavaScript variables. The values of those JavaScript variables can be manually set within the code, or retrieved from static or dynamic JSON resources.

AngularJs History

AngularJS is one of today’s hottest JavaScript MVC ( MVVM ) Frameworks . AngularJS was originally developed in 2009 by Misko Hevery and Adam Abrons at Brat Tech LLC, Now it was officially supported & maintained by Google ( MIT License ). Misko Hevery is a Google employee, started to work with AngularJS in 2009. The idea turned out very well, and the project is now officially supported by Google.

AngularJS Features

Angular has the following key features which makes it one of the powerful frameworks in the market.

1. MVC – The framework is built on the famous concept of MVC (Model-View-Controller). This is a design pattern used in all modern day web applications. This pattern is based on splitting the business logic layer, the data layer, and presentation layer into separate sections. The division into different sections is done so that each one could be managed more easily.
2. Data Model Binding – You don't need to write special code to bind data to the HTML controls. This can be done by Angular by just adding a few snippets of code.
3. Writing less code – When carrying out DOM manipulation a lot of JavaScript was required to be written to design any application. But with Angular, you will be amazed with the lesser amount of code you need to write for DOM manipulation.

Unit Testing ready – The designers at Google not only developed Angular but also developed a testing framework called "Karma" which helps in designing unit tests for AngularJS applications.

AngularJS Architecture

Angular.js follows the MVC architecture, the diagram of the MVC framework as shown below.

• Models are used to represent your data. The data in your model can be as simple as just having primitive declarations. For example, if you are maintaining a student application, your data model could just have a student id and a name. Or it can also be complex by having a structured data model. If you are maintaining a car ownership application, you can have structures to define the vehicle itself in terms of its engine capacity, seating capacity, etc.
• The Controller represents the layer that has the business logic. User events trigger the functions which are stored inside your controller. The user events are part of the controller.

Views are used to represent the presentation layer which is provided to the end users.

Advantages And Disadvantage of AngularJS:

Advantages

1. It provides the facility to create Single Page Application in a very clean and maintainable way.
2. It provides the data binding facility to HTML thus giving user a rich and responsive experience
3. Its code is unit testable.
4. It uses dependency injection.
5. It provides reusable components.
6. AngularJS uses pure html pages for view and JavaScript for controllers

Disadvantages 

1. Not Secure – As discussed earlier AngularJS is a JavaScript framework so the applications written in AngularJS are not safe. We have to provide server side authentication and authorization to create a secure application.

2. Not degradable − User will see the basic page only if JavaScript is disabled.

Conclusion: 

Angular is way popular, dynamic, and most adaptable by the enterprises. Every project we did with AngularJS — and we mean every single one — was designed and developed to build an enterprise solution with the same methodology and belief. AngularJs is a great choice, for javascript framework as it allows advanced web application development. It presents all the information in a fresh way easy-to-digest way.