function table_name($tablename) {        if(!empty($this->map) && !empty($this->map[$tablename])) {            $id = $this->map[$tablename];            if(!empty($this->config[$id]['tablepre'])){                $this->tablepre = $this->config[$id]['tablepre'];            }            if(!$this->link[$id]) {                $this->connect($id);            }            $this->curlink = $this->link[$id];        } else {            $this->tablepre = $this->config['1']['tablepre'];            $this->curlink = $this->link[1];        }        return $this->tablepre.$tablename;    }