RegEx to check for non-Latin characters

Dear List, For a Form Validation process, I need a function to avoid Latin characters to be provided as the first or last name. Since we expect our users to enter their personal info in Persian. Do you know any regular expression to provide this functionality? 1) Regex to check whether there are Latin and Numerical characters in a string. 2) Regex to check whether the string only consists of certain characters. Thanks you very much in adnvace, Kind regards, -behzad