OnChanges
OnChanges
Stable Interface
What it does
Lifecycle hook that is called when any data-bound property of a directive changes.
How to use
.
@Component({selector: 'my-cmp', template: `...`}) class MyComponent implements OnChanges { @Input() prop: number; ngOnChanges(changes: SimpleChanges) { // changes.prop contains the old and the new value... } }
Interface Overview
interface OnChanges { ngOnChanges(changes: SimpleChanges) : void }
Interface Description
ngOnChanges
is called right after the data-bound properties have been checked and before view and content children are checked if at least one of them has changed. The changes
parameter contains the changed properties.
Interface Details
ngOnChanges(changes: SimpleChanges) : void
exported from core-index, defined in core/src/metadata/lifecycle_hooks.ts
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Licensed under the Creative Commons Attribution License 4.0.
https://angular.io/docs/ts/latest/api/core/index/OnChanges-interface.html