This document provides an overview of key differences between AngularJS 1.x and Angular 2.0. It discusses changes to change detection, routing, services, directives, transpilation to ES5, and dependency injection. Transpilation of Angular 2 code from ES6 to ES5 for browser compatibility is recommended using tools like Babel. Components, services, and directives are defined differently in Angular 2 compared to 1.x. Routing is now done at the component level rather than using routes.

1.  

2. Nagaraju Sangam
AngularBuff@ ADP
nagaraju_sangam@yahoo.co.i
n
Speakerat various FrontEnd Meetups
nagaraju.sangam@gmail.com

3.  Errors?? God Only Knows 
 Errors are ignored in templates. Even God Doesn’t know..!!! 
 Different ways to create different things: provider, factoy, service, value, constant
 Opinionated, Verbose, steep learning curve
 Everything is singleton 
 Not an elegant dependency injection, crazy work arounds for minification 
 Route: No built-in partial view support using ng-route
 Issues with Scope & child scopes
 Dirty checking
 Issues with digest cycles: $scope.apply();
 Two way data binding: Max of 2000 bindings.
 jqLite: No direct modification of dom??? dropped in 2.0 
 Directives supports “EACM” only no way to use selectors.
 modules : No built-in module loading
 No inheritance supported for angular modules

4.  To knock off many old components.
i.e. $scope, $rootScope, services, controllers, modules, jqLite etc.
 To leverage latest ECMA Script standards
 To leverage modern browser capabilities.
 Improve many areas with different approaches with past expirience.

5. Routing
Services
DI
Directives
ES5 & ES6+
Server Side
Angular
Change Detection
Web workers
Promises
Testing
Material design
RxJsTypes
Annotations

6. Angular JS 1.x Angular JS 2.0
Controllervs
$scopeecives
Component Class
Service Simple Class
Angular Modules ES6 Modules
Directive

7.  Converts source code from one programming language to other.
 ES6 to ES5 Transpilers
 Traceur
 Typescript
 Flow
 Babel
 Dart
 Angular2 apps should be written in ES6. since the browsers doesn’t support ES6 you can use any of the above
transpiler to convert it to ES5.
 Google and Microsoft are working together to make type script as a standard for developing angular2.0 apps.
http://www.2ality.com/2014/10/typed-javascript.html

8. ES
6
ES
5
Type
s
Annotatio
ns
AtScript
Type script

9. Angular 1.X Angular 2.0
 Change detection happens at DOM node level
only
 Change in one node triggers dirty checking at all
other nodes.
 Change detection can happen at component level as
well.
 Change in one component triggers dirty checking in
other nodes below the current node…
 Change detection strategy can be configured at
component level

10. @Component({
selector: <string>‘,
changeDetection: ‘<string>’
})
@View({
template: ‘<string>’
})
export class <className>{
constructor() {
}
}
 The changeDetection property defines, whether the change detection will be
checked every time or only when the component tells it to do so.
Watchtower.js is used for change detection.

11.  Angular 2.0 doesn’t have two-way data binding like 1.x
 two-way data binding can be achieved with the combination of event & property bindings:
<input type='text' [value]=‘ename' (keyup)=‘ename=$event.target.value' />
 In short :
<input type='text' [value]=‘ename' (keyup)=‘ename=$event.target.value' />

12.  Routing happens at component level, for each different route different component can be loaded into RouterOutlet
directive, it is similar to ui-view in angular 1.X.
@RouteConfig([
{ path: '/', redirectTo: '/sponsers' },
{ path: '/sponsers', component: Sponsers, as: 'sponsers'}, //sponsers & attendees are components
{ path: '/attendees', component: Attendees, as: 'attendees'}
])
<router-outlet></router-outlet>
 Router-Link is similar to hg-href in 1.X.
<a [router-link]="['/attendees']" router-params="">attendees</a>
 JSON based route config
 404 support
 QueryString support
 Lyfecycle events
 routeResolver

13.  Component Directives
 Decorative Directives
 Template Directives
Following annotations are used to create directives.
 @Directive
 @Component
http://www.2ality.com/2014/10/typed-javascript.html

14. Service is a simple ES6 class in Angular2, these services should be injected into components via
Dependency Injection.
Sponsers-Service.ts
export class SponsersService{
constructor() {
}
getData(){
return ['cisco','intel','flipkart'];
}
}
http://www.2ality.com/2014/10/typed-javascript.html

15. http://www.2ality.com/2014/10/typed-javascript.html
Http is available as a separate module in alpha 35: https://code.angularjs.org/2.0.0-alpha.35
Eg:
import {Http, httpInjectables} from 'angular2/http';
@Component({selector: 'http-app', viewBindings: [httpInjectables]})
@View({templateUrl: 'people.html'})
class PeopleComponent {
constructor(http: Http) {
http.get('people.json')
.toRx()
.map(res => res.json())
.subscribe(people => this.people = people);
}
}

16.  Dependencies can be specifies as parameters: eg: function(@Inject(<svcName>) s)
 Component dependencies should be listed in bindings property of @Component annotation.
 Template dependencies should be listed in directives property of @View annotation.
http://www.2ality.com/2014/10/typed-javascript.html
import {Component, View, Injector} from 'angular2/angular2';
import { NgFor } from 'angular2/angular2';
import {SponsersService} from 'services/sponsers-service';
@Component({
selector: 'sponsers',
bindings:[SponsersService]
})
@View({
template: '<ul><li *ng-for="#item of data">{{item}}</li></ul>',
directives:[NgFor]
})
export class Sponsers {
data;
constructor(@Inject(SponsersService) s) {
this.data = s.getData();
}
}

17. Main-thread
(Browser+App+Angular Dom renderer)
messages
Child thread
(Angular stuff – house keeping etc)

18.  http://angular.io
 www.victorsavkin.com
 www.tryangular2.com
 http://www.syntaxsuccess.com/viewarticle/routing-in-angular-2.0
 http://blog.thoughtram.io/angular/2015/06/16/routing-in-angular-2.html

19. https://github.com/nasangam