What does Onchange do in Angular?
One of the great features of Angular is its ability to handle onchange events. Whether you're using a model-driven form or a template-driven form, onchange events give you the ability to respond to user input in real-time. Now we'll take a look at what onchange events are and how they work in Angular. We'll also explore some use cases for onchange events so that you can see how they can be used in your own applications. Onchange does exactly what you'd think - it changes something! In Angular, onchange is used to register a change event listener on an element.
ngchange angular 8
import { Component } from '@angular/core';
@Component({
selector: 'my-app',
template: `
<input type="number" [ngModel]="percent" (ngModelChange)="onPercentChange($event)" />
`,
styleUrls: [ './app.component.css' ]
})
export class AppComponent {
percent = 20;
onPercentChange(percent: number) {
console.log('here');
this.percent = percent;
}
}
onchange event in angular
<input [value]="foo" (change)="changeFn($event)">
<input [ngModel]="bar" (ngModelChange)="modelChangeFn($event)">
angular onChange onChanges SimpleChanges
export class MyClassName implements OnInit,OnChanges {
@Input() documents: Document[] = [];
.....
ngOnChanges(changes: SimpleChanges){
console.log("changes ", changes)
if(changes.documents){
console.log("changes2 ", changes)
}
}
Change is inevitable, whether in our personal lives or in the programming world. And if you're an Angular developer, then you know that one of the most important aspects of change detection is the onChange event.