validateEmail(email) { const regularExpression = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/; return regularExpression.test(String(email).toLowerCase()); }
<input type="email" name="email" ngModel email> <input type="email" name="email" ngModel email="true"> <input type="email" name="email" ngModel [email]="true">