function get_file_type($filename){$type = substr($filename, strrpos($filename, ".")+1);return $type;}方法2:function get_file_type($filename){ $type = pathinfo($filename); $type = strtolower($type["extension"]); return $type;}方法3:function get_file_type($filename){ $type =explode("." , $filename); $count=count($type)-1; return $type[$count];}希望本文所述对大家的php程序设计有所帮助。