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A callback method that performs change-detection, invoked after the default change-detector runs.

The default change-detection algorithm looks for differences by comparing bound-property values by reference across change detection runs. You can use this hook to check for and respond to changes by some other means.

When the default change detector detects changes, it invokes ngOnChanges() if supplied, regardless of whether you perform additional change detection. Typically, you should not use both DoCheck and OnChanges to respond to changes on the same input.

ngDoCheck(): void


The following snippet shows how a component can implement this interface to invoke it own change-detection cycle.

@Component({selector: 'my-cmp', template: `...`})
class MyComponent implements DoCheck {
  ngDoCheck() {
    // ...