How do I share data between components in Angular 2?

Question

In Angular 1.x.x you simply ask for the same service and you end up with the same instance, making it possible to share the data in the service.

Now in Angular 2 I h

Answer 1

You must use inputs and outputs of a @Component decorator. Here is the most basic example of using both;

import { bootstrap } from 'angular2/platform/browser';
import { Component, EventEmitter } from 'angular2/core';
import { NgFor } from 'angular2/common';

@Component({
  selector: 'sub-component',
  inputs: ['items'],
  outputs: ['onItemSelected'],
  directives: [NgFor],
  template: `
    

      {{ item }}
      Select
    
  `
})

class SubComponent {
  onItemSelected: EventEmitter;
  items: string[];

  constructor() {
    this.onItemSelected = new EventEmitter();
  }

  select(i) {
    this.onItemSelected.emit(this.items[i]);
  }
}

@Component({
  selector: 'app',
  directives: [SubComponent],
  template: `
    

      
      
    
  `
})

class App {
  items: string[];

  constructor() {
    this.items = ['item1', 'item2', 'item3'];
  }

  itemSelected(item: string): void {
    console.log('Selected item:', item);
  }
}

bootstrap(App);