What is the best method for interacting with "Components" in Angular 2-6?

Here are some methods I have been using:

  • @Input/@Output | Communication between parent and child components
  • @ViewChild | Communication with child components
  • @Injectable Service | Sharing data across components
  • rxjs/behaviorsubject | Data sharing among components

I came across an @Injectable component example, but I am unsure if it is another way to share component data.

I aim for the most efficient and clean approach(es) to share variables and methods between components without compromising performance or creating confusion.

I am considering data sharing in the following manner, though I am uncertain about its efficiency when dealing with multiple components:

PARENT

import { Component, OnInit, ViewChild, AfterViewInit } from '@angular/core';
import { ChildComponent } from './child/child.component';

@Component({
    selector: 'app-parent',
    templateUrl: './parent.component.html',
    styleUrls: ['./parent.component.scss']
})
class ParentComponent implements OnInit, AfterViewInit {
    public instance: ParentComponent;
    @ViewChild(ChildComponent) childComponent;

    constructor() {
        this.instance = this;
    }

    doSomethingWithParentMethod(strData: string) {
        console.log('parent data: ' + strData);
    }

    ngOnInit(): void {
    }

    ngAfterViewInit() {
        this.childComponent.doSomethingMethod('pass data to child in string type');
    }
}

In the Parent HTML file:

<app-child [parent]="instance"></app-child>

CHILD

@Component({
    selector: 'app-child',
    templateUrl: './child.component.html',
    styleUrls: ['./child.component.scss']
})
class ChildComponent {
    @Input() parent;

    public function doSomethingMethod(strData: string) {
        console.log('child data: ' + strData);
    }

}

Answer №1

Utilize @Injectable Service to easily share data between components

The functionality of this service can be adjusted based on specific needs, but its primary purpose is for seamless data transfer.

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