import { Component } from '@angular/core' ; import { FormControl , Validators } from '@angular/forms' ; title @ Component ( { selector : 'form-field-error-example' , templateUrl : 'form-field-error-example.html' , styleUrls : [ 'form-field-error-example.css' ] , } ) export class FormFieldErrorExample { email = new FormControl ( '' , [ Validators . required , Validators . email ] ) ; getErrorMessage ( ) { return this . email . hasError ( 'required' ) ? 'You must enter a value' : this . email . hasError ( 'email' ) ? 'Not a valid email' : '' ; } }