function isEmpty(a){return a.length==0||a==null}function isAlpha(a){if(isEmpty(a))return false;var b=/^[a-zA-Z., ]*$/;return b.test(a)}function isAlphaNumeric(a){if(isEmpty(a))return false;var b=/[a-z]|[A-Z]|[0-9]|\s|[_]/;return b.test(a)}function isNumeric(a){if(isEmpty(a))return false;var b=/[0-9]/;return b.test(a)}function isEmailAddress(a){if(isEmpty(a))return false;var b=/^.+\@.+\..+$/;return b.test(a)}
function isUSZip(a){if(isEmpty(a))return false;var b=/(^\d{5}$)|(^\d{5}-\d{4}$)/;return b.test(a)};