I have been searching for code to do an input mask for a telephone field in the format of xxx-xxx-xxxx. Found a post from 14+ years ago that placed code in " components/com_rsform/controller/validation.php". Code was this:

function phone($phone)
{
list($number1,$number2,$number3)=split("-",$phone,3);
if($phone=='' || strlen($phone)!=10 || !(is_numeric($number1)) || !(is_numeric($number2)) || !(is_numeric($number3)) || strlen($number3)!=2) return false;
if(ereg('^([0-9]{4})-([0-9]{4})-([0-9]{3})$', $phone))
return false;
else
return true;
}

I created the file in the directory indicated and copied the code into it. The code had no impact on the user entry for a phone number field or in the data stored. The text field is set to validate a telephone number. The field Validation/Required attribute is set to "No".

What am I missing or has something changed in the RS Forms code since the previous post?