[required] validation directive
A directive that adds the required
validator to any controls marked with the
required
attribute. The directive is provided with the NG_VALIDATORS
multi-provider list.
Adding a required validator using template-driven forms
<input name="fullName" ngModel required>
required
#
@Input() get required(): boolean|string
Tracks changes to the required attribute bound to this directive.
required
#
set required(value: boolean|string)
validate
#
validate(control: AbstractControl): ValidationErrors|null
Method that validates whether the control is empty. Returns the validation result if enabled, otherwise null.
registerOnValidatorChange
#
registerOnValidatorChange(fn: () => void): void
Registers a callback function to call when the validator inputs change.