Find an element by ID from another component in Angular 17

Getting an element by ID from another component in Angular can be achieved using a combination of component communication methods and DOM manipulation techniques. Here's a step-by-step approach:

1. Establish Communication: Determine the most suitable communication method between the components. Options include:

-   **Input/Output Decorators (@Input/@Output):** Pass the element reference or its ID as an input property to the child component.

-   **ViewChild Decorator:** Inject the child component using @ViewChild and access its element reference.

-   **Event Binding:** Use event binding to trigger a callback function in the parent component, passing the element reference or ID as an event argument.

-   **Services:** Create a shared service that both components can access to store and retrieve the element reference or ID.

1. Identify the Target Element: Determine the component that contains the element you want to access and its ID.

2. Access the Element Reference: Based on the chosen communication method, retrieve the element reference or ID from the target component.

3. Manipulate the Element: Once you have the element reference, you can manipulate it using DOM manipulation techniques like document.getElementById() or the nativeElement property of the ElementRef.

Here's an example using Input/Output decorators:

// ParentComponent.html
<app-child-component [elementId]="'my-element'"></app-child-component>

// ChildComponent.ts
@Input() elementId: string;

@ViewChild('myElement', { read: ElementRef<HTMLElement> }) elementRef: ElementRef;

ngOnInit() {
  const element = document.getElementById(this.elementRef.nativeElement.id);
  // Manipulate the element using `element`
}

Remember to import the necessary dependencies, such as ElementRef and ViewChild, to access the DOM elements.

Here is a step-by-step tutorial on how to get an element by ID from another component in Angular:

Step 1: Establish Communication between the Components

There are several ways to establish communication between components in Angular. For this tutorial, we will use the @ViewChild decorator. This decorator allows you to access the child component's element reference from the parent component.

Step 2: Create a Reference to the Child Component

In the parent component, add the @ViewChild decorator to a property that will hold a reference to the child component. Make sure to specify the read option to get the ElementRef of the child component's element.

import { Component, ViewChild, ElementRef } from '@angular/core';

@Component({
  selector: 'app-parent',
  template: `
    <app-child #childComponent></app-child>
  `,
})
export class ParentComponent {
  @ViewChild('childComponent', { read: ElementRef<HTMLElement> }) childElementRef: ElementRef<HTMLElement>;
}

Step 3: Access the Element in the Child Component

In the child component, use the ElementRef to access the element's native DOM element.

import { Component, ElementRef } from '@angular/core';

@Component({
  selector: 'app-child',
  template: `<div id="my-element">Child Component Element</div>`,
})
export class ChildComponent {
  constructor(private elementRef: ElementRef<HTMLElement>) {}

  ngOnInit() {
    const element = this.elementRef.nativeElement;
    // Manipulate the element using `element`
  }
}

Step 4: Get the Element from the Parent Component

Once communication is established, you can access the child component's element from the parent component.

ngOnInit() {
  const element = this.childElementRef.nativeElement.getElementById('my-element');
  // Manipulate the element using `element`
}

This approach allows you to access and manipulate the element directly from the parent component.

• Date: 13 Nov 2023