@angular/forms

AsyncValidator

interface

An interface implemented by classes that perform asynchronous validation.

API

Usage Notes

  
    interface AsyncValidator extends Validator {}

Promise<ValidationErrors | null> | Observable<ValidationErrors | null>

Method that performs async validation against the provided control.

@paramcontrolAbstractControl<any, any>

The control to validate against.

@returnsPromise<ValidationErrors | null> | Observable<ValidationErrors | null>

void

Registers a callback function to call when the validator inputs change.

@paramfn() => void

The callback function

@returnsvoid