Upgrade from AngularJS to Angular with ngUpgrade

Angularjs is an open-source JavaScript web application framework maintained by Google and a community of individuals and corporations. Angular, on the other hand, is a Javascript single-page application (SPA) toolkit which can be integrated into any HTML project. A lot has changed in the last year for developers who use AngularJS – Angular was released as official version 1.0 at end of September 2017 following the upgrade from angular-cli to ngUpgrade by default with plugin support included in this release.

The “migrate angularjs to angular 11” is a tool that allows users to upgrade their AngularJS applications with minimal effort. The tool will automatically detect and migrate your application’s codebase, data, and assets from the old framework to the new one.

Upgrade from AngularJS to Angular with ngUpgrade

Hello, programmers. Although the older versions of Angular that use JavaScript are still quite popular among developers, the newer versions of Angular that use TypeScript are rising in popularity every day. In this post, I’ll answer the issue of how to use ngUpgrade to complete an Angular migration.

ngUpgrade is a feature of Angular 2 that allows the framework’s next version and predecessors to run in parallel. As a result, it’s a good starting point for a creeping migration.

Since the introduction of Angular 2, developers have been wondering how they might prepare their AngularJS apps for the update. One solution is the ngUpgrade component included with Angular 2. It enables AngularJS and 2 to operate in parallel, laying the groundwork for a gradual migration. Developers may use the tool to write new Angular 2 application pieces without needing to move the prior components right away.

This article uses an example to demonstrate the technique. The source code for this project may be available on GitHub. It compiles the constructs built with it for execution in the browser according to ECMAScript 5 and utilizes the TypeScript language for both AngularJS and Angular 2.

The structure of the application is shown in the diagram below.

As a result, it’s an AngularJS application, which is also required for ngUpgrade to work. However, components (directives) and services created using both AngularJS and Angular 2 are utilized inside the application. The framework version used may be seen in the component image at the upper left.

They must be degraded in order to utilize Angular 2 constructs in AngularJS. This implies that developers wrap them in a ngUpgrade wrapper to make them seem to the outside world as an AngularJS structure. This occurs in the scenario at hand with FlugCard, FlugService, and the Passenger Search component. On demand, NgUpgrade additionally delivers AngularJS constructs wrapped in an Angular 2 wrapper. There is mention of an upgrade in this scenario. This is required for the PassengerCard and PassengerService in the current case.

What is the best way to set up the task and start the process?

The sample uses script references to include both the AngularJS and Angular 2 bundles, including ngUpgrade. TypeScript is used to create the application. The program uses the module loader System to load the ECMAScript-5 files that were built from the sources. js:

(‘app / app’) System.import if (console.error.bind (this)); if (console.error.bind (this)); if (console

Because TypeScript uses the ECMAScript 2015 modular structure, each file declares its dependencies using import instructions, the application simply has to request that the app / app.js file be loaded. It registers the separate structures, such as controllers and services, as is typical in AngularJS applications. It also takes care of the application’s initialization. However, the method of the same name from the so-called UpgradeAdapter by ngUpgrade is utilized instead of angular.bootstrap. It’s the key to getting the parallel operation to work. ngUpgrade, on the other hand, does not have an equivalent to the ng-app property for bootstrapping. Because the upgrade adapter is required in numerous locations throughout the program, it is best to create it in a separate file:

upgrade-adapter.ts (upgrade-adapter.ts) (upgrade-adapter

‘angular2 / upgrade’ import UpgradeAdapter;

upgradeAdapter = new UpgradeAdapter (); export const upgradeAdapter = new UpgradeAdapter ();

The UpgradeAdapter may then import the file app.ts and utilize it to bootstrap the application:

// app.ts

‘./upgrade-adapter’ import upgradeAdapter;


angular.module (‘app’, [‘ui.router’]) var app = angular.module (‘app’, [‘ui.router’]) var app = angular.module ( ;


(document.body, [‘app’]); upgradeAdapter.bootstrap

What are the differences between upgrades and downgrades?

The upgrade adapter’s downgradeNg2Component function is used to downgrade the Angular 2 component Passenger Search discussed before. The returned wrapper is registered as a directive using App.directive:

// app.ts

app.directive (‘passenger search,’,’,’,’,’,’,’,’,’,’,’,’,

<any> upgradeAdapter.downgradeNg2Component (Passenger Search));

Its configuration gets a state with a template depending on it so that the UI router may activate it:

$ stateProvider is a variable.

.state (‘passenger-search,’,’,’,’,’,’,’,’,’,’,’,’,

    ‘/ passenger-search’, ‘/ passenger-search’, ‘/ passenger-search’, ‘/ passenger-

    template: ‘<passier-suchen> </passagier-suchen>’


The following two source code samples show another way to use an Angular 2 component. In the overview image, this is the flight card. App.ts, like the FlugSuche component, handles the downgrading and registration:

// app.ts

app.directive (‘flugCard ‘,’,’,’,’,’,’,’,’,’,’,’,’

<any> upgradeAdapter.downgradeNg2Component (FlugCard));

The following is how you utilize such a directive in an Angular 1 template:

/ (ng1)

<div class = “col-sm-4” style = “padding: 10px;” ng-repeat = “f in ↵

 FlugSuchen.flege “>

    <flight card

        “f” is the value of [item].

        “flightSuchen.selectedFlug” [selected-item] = “flightSuchen.selectedFlug”

        (selected-item-change) = “flightSuchen.select ($ event)”>



Please keep in mind that the data binding is built up using the Angular 2 syntax. As a result, square brackets indicate a one-way binding, whereas round brackets denote an event binding. A two-way bond is the result of combining both. Using selected-item and selected-item-change, the following example demonstrates this.

In Angular 1, there is an Angular 2 service.

Angular 2 services are equivalent to related components in terms of use. However, the UpgradeAdapter requires that providers for the service and its dependents be registered:

// app.ts

(FlugService); upgradeAdapter.addProvider;

(HTTP PROVIDERS); upgradeAdapter.addProvider;

Because FlugService makes use of Angular 2’s HTTP service, the example registers the HTTP PROVIDERS array, which includes the necessary providers. Furthermore, the downgradeNg2Provider function manages the service’s downgrading. The wrapper returned by it is then registered by app.factory:

upgradeAdapter.downgradeNg2Provider (FlugService)); app.factory (‘flugService ‘, upgradeAdapter.downgradeNg2Provider (FlugService));

Existing AngularJS constructions must be upgraded using upgradeNg1Provider: in order to be used in Angular 2 components or services.

// app.ts

app.service (‘passenger service’, ‘passenger service’); app.service (‘passenger service’, ‘passenger

(‘passengerService’); upgradeAdapter.upgradeNg1Provider

After that, Angular 2 components and services may use dependency injection to request the service. Because optional type requirements aren’t used in AngularJS 1.x, the desired service’s name must be supplied using the Inject decorator:

/ passenger-search.ts/ (ng2)

@Component ([…]) @Component ([…]) @Component ([…]) @Component

traveler search by export class

    constructor ( constructor

        private passengerService: @Inject (‘passengerService’)

         Service to Passengers

        shopping cart service) (private shopping cart service)



If developers wish to reuse an AngularJS directive in a new Angular component, upgradeNg1Component must be used. The function accepts the name of the directive’s registration and returns an Angular 2 wrapper. After that, all the component needs to do is add it to its list of directives.

/ passenger-search.ts/ (ng2)


    ‘passenger search’ is a selection.

    ‘app / passenger-search / passenger-search.html’, templateUrl: ‘app / passenger-search / passenger-search.html’,

    [upgradeAdapter.upgradeNg1Component (‘passengerCard’)] directives


traveler search by export class



The directive may be referenced in the component’s template. It does this by using an element with the name of the directive’s initial registration.

/ passenger-search.html/ (ng2)


<div * ngFor = “# p of passengers” class = “col-sm-4” style = “padding: 10px;”>

    <passenger card

        ‘p’ as [item]

        “selectedPassagier” is the value of [selectedItem].

        (selectedItemChange) = “select ($ event)”>




The bindings are built up using the Angular 2 notation in this scenario as well.

In order to be utilized in Angular 2, an AngularJS directive must follow specific best practices. The relatively new attributes controllerAs and bindToController, for example, are recommended. Furthermore, the link and compile methods should be avoided, particularly as Angular 2 lacks an equivalent:

/ passenger-card-factory.ts/ (ng1)

class export PassengerCardFactory is a company that makes passenger cards.

    ng.IDirective ng.IDirective ng.IDirective ng.IDirective ng.IDirective ng.

        make a comeback

            ‘app / passenger-card / passenger-card.html’, templateUrl: ‘app / passenger-card / passenger-card.html’,

            ‘vm’, ‘controllerAs’, ‘controllerAs’, ‘controllerA

            sphere of influence:


                ‘=’ for selectedItem


            true, bindToController: true, bindToController: true, bindToController

            function () () () () () () () () () ()

                null; this.item; this.item; this.item; this.item;

                this.select = () => {

                    this.item = this.selectedItem;


PassengerCardFactory.create app.service (‘passengerCard’);

Angular 1.5’s module.component

Angular provides an alternative to module.directive, which enforces the recommended practices outlined above, with the module.component convenience function.


As a result, ngUpgrade allows AngularJS and Angular 2 to run in parallel, allowing for a creeping migration. While Angular 2 may be used to create new sections right now, current constructions cannot be migrated right away.

The fact that ngUpgrade ships with Angular 2 has a great symbolic significance. It demonstrates that the Angular team hasn’t forgotten about their most crucial success element. This indicates a robust community, which, despite the fresh start of Angular 2, must continue to support AngularJS applications.

The “angularjs to angular 10 migration” is a process that can be used when upgrading from AngularJS to Angular. The process allows for the migration of modules, controllers, and services.

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