angularjsHow do I use the onChanges feature of AngularJS?

The onChanges feature of AngularJS allows you to watch for changes in an object and respond to them. It is typically used to detect and respond to changes in a component's input properties.

Here is an example of using onChanges:

@Component({
  selector: 'app-example',
  templateUrl: './example.component.html',
  styleUrls: ['./example.component.css']
})
export class ExampleComponent implements OnChanges {
  @Input() name: string;

  ngOnChanges(changes: SimpleChanges) {
    if (changes.name) {
      console.log(`Name changed to ${changes.name.currentValue}`);
    }
  }
}

In this example, the onChanges feature is used to detect changes in the name input property. When the name property is changed, the ngOnChanges function will be called, and the new value of the name property will be logged to the console.

Code explanation

1. @Component: This is a decorator used to define the component.
2. @Input() name: string: This is an input property of the component.
3. ngOnChanges(changes: SimpleChanges): This is a function that is called when an input property is changed.
4. if (changes.name): This checks if the name input property has changed.
5. console.log(Name changed to ${changes.name.currentValue}): This logs the new value of the name property to the console.

Here are some ## Helpful links

• Angular Documentation - OnChanges
• Angular Tutorial - OnChanges

Edit this code on GitHub