Form Php

     if(isset($_GET['submit'])) {
          if(preg_match("/^\(([2-9][0-9]{2})\)[2-9][0-9]{2}-[0-9]{4}$/i",
                                  $_GET['phone']) != 1) {
               echo "The phone field was invalid
";
          }
     } else {
          /* Code to process form here */
     }
?>

Elementary form validation

" METHOD=GET>

Phone: 
(ex. (333)555-1212)