DoCheck
DoCheck
What it does
Lifecycle hook that is called when Angular dirty checks a directive.
How to use
.
@Component({selector: 'my-cmp', template: `...`}) class MyComponent implements DoCheck { ngDoCheck() { // ... } }
Interface Overview
interface DoCheck { ngDoCheck() : void }
Interface Description
ngDoCheck
gets called to check the changes in the directives in addition to the default algorithm. The default change detection algorithm looks for differences by comparing bound-property values by reference across change detection runs.
Note that a directive typically should not use both DoCheck
and OnChanges
to respond to changes on the same input, as ngOnChanges
will continue to be called when the default change detector detects changes.
See KeyValueDiffers
and IterableDiffers
for implementing custom dirty checking for collections.
Interface Details
ngDoCheck() : void
exported from core-index, defined in core/src/metadata/lifecycle_hooks.ts
© 2010–2017 Google, Inc.
Licensed under the Creative Commons Attribution License 4.0.
https://angular.io/docs/ts/latest/api/core/index/DoCheck-interface.html