If you’re looking to upgrade your AngularJS application to modern day web development standards, it helps to know what is the right approach and the right tools to use. In this article, I will explain the differences between AngularJS and Angular. Then, I will explain why you need to migrate your project from AngularJS to Angular and then describe migration tools available to make your life easier.

What is AngularJS?

AngularJS is a web and mobile application framework used to develop Single-page applications. This framework was developed by Google engineers and is based on the Model-View-Controller.

The MVC architecture comprises of;

Model – The data structure that organizes data inputs from the controller.

View – The view displays raw data and information.

Controller – The controllers handles instructions and interactions within the data model.

The first version of AngularJS was released in 2012. As time progressed, new updated versions were launched. However, as more versions were released over the years, a major rewrite was done that resulted in Angular 2.

To eliminate naming confusions, the Angular team decide that AngularJS would refer to any version between Angular 1.x to Angular 2. All versions above Angular 2.0 would simply be called Angular.

Why should you opt for Angular?

After its release in 2012, AngularJS gained in popularity. Initially, small scale developers were the main customers. Later, bigger software developing companies started using AngularJS for large scale purposes. At this point, developers started experiencing performance issues. In an interview in 2018, Stephen Fluin; a Google Angular engineer observed that AngularJS was not built for large-scale usage.

“There were millions of AngularJS developers and millions of AngularJS apps. The cracks started showing. If you wrote an AngularJS app the wrong way and had thousands of things on the screen, it ended up getting very slow. The architecture was just not designed with this kind of large-scale usage in mind.

After Angular 2, it was evident that Google has adopted a revolutionary approach and as a result, there are efforts to encourage developers to migrate from AngularJS to Angular.

Difference between AngularJS and Angular

Majority of front-end developers are familiar with angular framework. With the different versions, it is crucial for developers to determine which angular version to use for their project. 

So, which Angular version is better and why?

The section below illustrates the difference between AngularJS and Angular.

Difference AngularJSAngular
Script It is based on JavaScript It is based on TypeScript. TypeScript is a superset of ECMAScript 6. TypesScript enjoys the benefits of ES6 like Lambda operators and Iterators. 
Controllers vs Components It enables developers to scope variables visible in both view and controller. It also supports rootScope where created variables are globally available.It does not support scope or controller concepts. However, its main architectural concept is the hierarchy of components. 
Template engine Has many directives and allows developers the liberty to specify custom directives.
It has standard directives that are implemented differently. 
Expression syntax AngualrJS has both the ng-model and ng-bind. Ng-model implements two-way binding while ng-bind implements one-way binding.Angular has only the ng-model. “[ ]” is used to implement one-way binding while “[( )]” is used to implement two-way binding. “( )” is used for event binding while “[ ]” is used in event binding. 
Architecture It is based on the Model-View-Controller. The MVC model organizes data logic, exhibits applications behaviour and stipulates the rules. 
The View relays output information from the model. The controller transforms inputs into commands and then sends them to the view and the model. 
It uses components and directives instead of controllers and scope. The components and directives handles the application’s view and the page logic. 
Angular 2 has structural directives that transforms the DOM layout and attributive directives that transform the DOM element appearance.   
Mobile supportSupports on web applicationsSupports both web and mobile applications
Routing Uses $routeprovider.when() for routing configuration. Uses @RouteConfig{(…)} for routing configuration. 
Performance Has limited performance because it was meant for designers. Has enhanced high speed performance because it is built for designers and developers. 
Dependency Injection Does not support dependency injectionSupports hierarchical dependency injection with unidirectional tree-based change detection. 
Structure It is complex and difficult to manageHas better structures making it easy to manage 


Pros and Cons: Which version of Angular is best for you?


Angular JS

Advantages

  • Facilitates faster application development due to excellent MVC data binding. 
  • Angular JS has comprehensive resources such as plugins sufficient for front-end developers. Developers do not need to use other frameworks. 
  • Angular JS is very intuitive because it utilizes HTML as a declarative language.   
  • Angular JS is very flexible as it can develop both iOS and Android applications. 

Disadvantages

  • Angular JS has multiple ways of achieving the same thing making complex and difficult to use. 
  • It has poor scalability
  • It has performance issues when handling many requests. 

Angular 2

Advantages

  • Use of TypeScript enhances code optimization
  • Angular 2 supports mobile-oriented applications
  • Enhances dependency injection 
  • Avails varying scripting languages like ES6, ES5 and TypeScript. 
  • Facilitates code routing.

Disadvantages

  • It has a complex set up process compared to Angular JS.
  • It is not viable for small and simple web applications. 

Angular 4

Advantages

  • Enhances quick application development by providing templates. 
  • It is suitable when developing single-page web apps.
  • TypeScript assists in developing bulky apps. 
  • It is easy to write and test codes by providing a framework that accommodates unit system testing. 
  • Angular provides templates that allows developer to produce clean codes.  
  • It has a modular animation package. 
  • Angular produces applications that are compatible with both mobile and desktop. 

Disadvantages

  • It is slow when outputting large amounts of data. 

Why should I migrate to Angular?

Before making the great move there are questions you should ask yourself, what benefits will I get from the new framework? Migrating from one developer framework is not an easy decision to make but a careful evaluation of the framework you are migrating to gives a clear picture of the benefits it comes with.

Angular, being an evolution of AngularJS, it is better than its predecessor in creating better user interfaces. These are the reasons you should migrate your apps to Angular.

Flexible Architecture

The architecture of Angular is based on a hierarchy of services and components, a feature that was not present in AngularJS.  The hierarchical nature allows the elements to be reusable and makes it easier to test and maintain them.

Availability of Ready to use Angular Resources

WrapPixel Angular Mega Bundle

Wrappixel Angular Mega Bundle

AngularJS and Angular are open source and thus receive massive support from Google engineers and the developer community. At WrapPixel, we love the Angular framework and our community of developers have curated a master list of ready to use Angular Themes, Angular Dashboards, Angular Website Templates  and Angular Control Admin panels to help developers looking to migrate to the latest version of Angular.

If you’re an agency or a product development company looking to create multiple Angular Web apps or Admin Panels, the  Angular Mega Bundle is a must resource. It comes with more than 60 plugins, 1000s of Angular UI Components and pages, unique Angular Dashboards and 7+ Angular templates. The templates, clean documentation and dedicated support make Angular app development a breeze, even for novice developers.

Handheld device Support

AngularJS does not support development of handheld device apps. With the rapid increase in popularity of mobile device usage, you should consider migrating to Angular, which will enable you to develop mobile apps. Angular version 2 and the following versions offer mobile app support across all devices. They have features such as touch support, performance tuning, and low memory utilization among others, which are useful in solving mobile-related issues. Angular 7 has a modular design that significantly reduce the memory footprint on mobile devices.

Improved Speed&lt

With AngularJS, the code tends to be slower when running large applications due to a large number of scopes and bindings. The two-way binding cause delays and bottlenecks.

In Angular 2 and above, there was introduction of property binding, event binding and template binding, all which improve the performance of the app. Angular 6 uses a rendering engine called Ivy which introduces faster compilation, smaller-sized bundles, faster debugging and increased flexibility.

Better Structure

AngularJS is flexible but has low stability and manageability. Angular, having a component-based approach, has a precise way of exchange of data among the components. This will make it easier for you to seamlessly create and maintain large apps.

Angular allow use of modules. The module allows separation of code into smaller units depending on the use.  This makes it easier to understand where different elements are located. You can create different modules such as for login, user setting, and for shared components, each of which will import the required libraries and components.

Modules coupled with lazy loading create smaller pieces of code which are only loaded by the browser only when needed.  This makes load time faster by showing you what is needed at that time.

Consistency and flexibility

AngularJS is written in plain JavaScript which lacks type-checking feature making compile-time errors. Angular is written in TypeScript which offers consistency and flexibility. Since TypeScript is a superset of JavaScript, you will have an easy time since the syntax and approach is similar to what you already know. Typescript reduces runtime errors as they are recognizable before compilation takes place.

Material Design

In Angular 5, component design kit (CDK), the core of Angular Material component library, also facilitates the development teams to create their elements.  This element allows the creation of applications which are responsive and can run on different platforms. Additionally, the material design helps in developing an improved user interface.

Regular Updates

Angular development team provide regular updates to give your apps maximum stability. This also includes security patches which allows a secure development platform for secure applications devoid of vulnerabilities. The Angular development team uses a time-based publishing cycle and therefore they are able to release new and improved versions after every six months.

There are many substantial benefits of migrating from AngularJS to Angular. Angular generally will improve your experience through new features and this makes it worth migrating to.

Tools for migrating from Angular JS to Angular

Migration to Angular has been made easy by using these two tools; ngMigration Assistant and ngMigration Forum. These tools are meant to provide a correct migration process, by avoiding possible mistakes.

ngMigration Assistant

This is an analysis tool which is very easy to use. It uses a command line interface (CLI) with simple instructions to follow. ngAssistant analyses the AngularJS application and give a suitable recommendation on how to move your app to Angular. In other words, ngMigration helps to determine the best path to use when migrating from AngularJS to Angular.

ngMigration assistant provides a good starting point when you decide to migrate your project to Angular. When you run the tool, it analyses the code base and provide details on the size of the code, the complexity and the patterns used in the project. With this, the tool proposes the path to follow and provides instructions for you to follow in the preparation for the migration as shown below.

ngMigration Assistant

The main objective of ngMigration Assistant is to give you a simple, clear and constructive guidance on how to migrate your app or project. ngMigration Assistant can be used for any size of an app, whether big or small. Not all possibilities are taken into considerations, only the size of the code and its complexity.

Installing the ngMigration assistant is also an easy task.

Install globally, whether using npm or yarn using this commands

C:\Users\Leirtech\Desktop\migration assistant install 2.PNG

After a successful installation, run the program and it will scan the working or input directory, as shown I the command below

From that point the tool will start scanning the app and provide you with the necessary recommendations and steps to follow to migrate your app.

ngMigration Forum

This is a community hub composed of developers, users and entrepreneurs who discuss and share information on the best way to migrate from AngularJS to Angular.  This forum will provide you with a good starting point and the steps to take when conducting the migration.

From the forum, your migration questions will be expertly answered, useful tools identified and you will be directed to a migration solution. Also, you will learn, discuss and share information pertaining the migration to Angular.

The forum provides arrays of useful information, such as the importance of migrating to Angular from a technical and business perspective and the overview of the migration paths that you can use.

In the Forum you will find many migration paths consolidated over time, and many useful tools that help throughout the migration process.

AngularJS to Angular Migration

In-depth information is provided on all the migration paths where you can learn how they work, tools that will help you, examples and read any helpful content. There are also experts to help you with the path you decide to use, throughout the migration process.

The community works together to share their expertise and experience in the migration process. You are also encouraged to contribute to the forum and give helpful insights, tools, ask questions or provide answers pertaining to the migrations.

Migration approaches

Before migrating from Angular JS to Angular, it is good for developers to strategize how to migrate. A good migration strategy makes the migration process smooth and easy.

Angular complete rewrite

One migration strategy adopted by developers is the incremental approach. The incremental approach is suitable in incidences where the application is too large and might consume a lot of time during the migration process. This means that continuous support is needed for the application when migrating from Angular JS to Angular.

However, in instances where the application is small and can be migrated over a short time, then complete rewrite is the better approach.

A complete rewrite involves migrating an application to Angular without supporting the previous Angular JS version.

The migration approach selected relies on your objectives as a developer or as an entrepreneur. On several occasions, business require their applications to continue running without interruptions.

When migrating large applications, organizations should also consider splitting the applications across teams where each team migrates each section at different times.

Despite the migration tools available, migrating a project from AngularJS to Angular is not an easy process.

The section below describes Angular upgrade modules;

Module loader

Developers can employ the available module loaders such as SystemJS, Webpack or Browserify to upgrade their projects.

For a developer, you can break down your application code into individual file components. This helps you organize your large project into small structured files.

Loading all these files with a <script> into a HTML page is hectic and sometimes does not work efficiently.

To avoid these hectic process, it is good to employ a module loader. Module loaders like Webpack allows you to utilize the import and export features. These features specifies which code should be shared between various application parts. The CommonJS module loader enables users to use the require and module.exports features.

Migration to TypeScript

Angular uses TypeScript instead of JavaScript. When migrating applications from AngularJS to Angular, it is good to load the TypeScript compiler.

Loading the TypeScript compiler helps you to stop worrying about how to implement Typescript. It also helps you to start utilizing TypeScript in your loaded AngularJS code.

Using component Directives

In Angular, components provides the basis for building user interfaces. The various user Interface portions are categorised as components and then transformed into the expected user experience.

AngularJS applications implemented using Component directives are easier to migrate than applications developed using inferior features like ng-controller and ng-include.

Before migrating AngularJS to Angular, ensure that your AngularJS component directives has the following attributes;

  • Restrict: ‘E’ components that are utilized as elements.
  • Scope: {} is an isolate scope. Angular implements isolation and therefore, ensure your AngularJS components are also isolated to enhance compatibility. 
  • bindToController: {} ensure components are bound to controller instead of $scope.  
  • controller and controllerAs
  • template or templateUrl

The snippet below illustrates an AngularJS component directive that is fully compatible with the Angular architecture.

AngularJS Component Directive

If your component directives are not compatible with Angular, it is good to use component API to help you define the components easily.

Migrating using ngUpgrade

The ngUpgrade helps you compare AngularJs and Angular components in an app and combine them to operate seamlessly. The ngUpgrade allows you to conduct the migration in bits since the different frameworks coexists together.

ngUpgrade has an Upgrademodule that helps you to bootstrap and organize your hybrid applications. According to the AngularUpgrade Guide,

“When you use ngUpgrade, what you’re really doing is running both AngularJS and Angular at the same time. All Angular code is running in the Angular framework, and AngularJS code in the AngularJS framework.”

Bonus Tip: Must Have Resources for Angular development

As a developer or an entrepreneur, migrating from AngularJS to Angular is essential. Migrating will help you enjoy increased flexibility and scalability.

If you’re concerned about the number of manhours and development effort involved in building an Angular app, we have developed a wide range of Angular templates and Angular resources for you to choose from. These Angular templates will help save development time and avoid the high cost of developing everything from scratch.

Our Angular templates are trusted by thousands of customers all over the world. When you purchase our templates, you enjoy free support, wide range of plugins, multiple admin dashboards and seamless functionality.

If you feel that we’ve missed out on any Angular Hacks that can help make life easier for developers, please share in the comments, we’d love to hear from you.

If you are looking to hire angular developers, here is complete guide from Toptal.