= $m && mb_strlen($str) <= $n) { return true; } else { return false; } } public function isascii($str) { if (mb_detect_encoding($str) == "ASCII") { return true; } else { return false; } } public function isengnum($str) { return (preg_match("/^[a-zA-Z0-9]+$/", $str) == 1); } public function isnum($str) { return (preg_match("/^[0-9]+$/", $str) == 1); } public function validateDate($date, $format = 'Y-m-d H:i:s') { $d = DateTime::createFromFormat($format, $date); return $d && $d->format($format) == $date; } public function RemoveChars($str, $chars) { $chars = str_split($chars, 1); for ($i = 0; $i < count($chars); $i++) $str = str_replace($chars[$i], "", $str); return $str; } }