[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|stringTracks changes to the required attribute bound to this directive.
required#
set required(value: boolean|string)validate#
validate(control: AbstractControl): ValidationErrors|nullMethod that validates whether the control is empty. Returns the validation result if enabled, otherwise null.
registerOnValidatorChange#
registerOnValidatorChange(fn: () => void): voidRegisters a callback function to call when the validator inputs change.