title: Any simple way to apply one validation rule to all fields by Angular 6
body: <p>Consider a data model contains 20 string fields with different name ("name", "address", "company".. etc ), mapped to Angular front end as 20 input fields. Now the requirement asks to validate each fields that prevent user submit the form if any fields contain special characters.</p>
  
  <p>I can work out the regex pattern but just wondering any simple way to do one validator to all fields. </p>