一个简单的dao，实现基本的crud功能，可以继承扩展为实际业务的dao类，当然也可以直接使用
复制代码 代码如下:
_con == null) {
                $this->_con = @mysql_connect(localhost, root, 123456);
                if ($this->_con == false) {
                    echo(connect to db server failed.);
                    $this->_con = null;
                    return;
                }
                //$firephp->log(new dao object);
                @mysql_select_db(swan, $this->_con);
            }
        }
        public function table($tablename) {
            $this->_table = $tablename;
            return $this;
        }
        public function query($sql) {
            $result = @mysql_query($sql);
            $ret = [];
            if ($result) {
                while ($row = mysql_fetch_array($result)) {
                    $ret[] = $row;
                }
            }
            return $ret;
        }
        public function get($where = null) {
            $sql = select * from .$this->_table;
            $sql = $sql.$this->_getwherestring($where);
            //echo [get].$sql.
;
            return $this->query($sql);
        }
        public function insert($params) {
            if ($params == null || !is_array($params)) {
                return -1;
            }
            $keys = $this->_getparamkeystring($params);
            $vals = $this->_getparamvalstring($params);
            $sql = insert into .$this->_table.(.$keys.) values(.$vals.);
            //echo [insert].$sql.
;
            $result = @mysql_query($sql);
            if (! $result) {
                return -1;
            }
            return @mysql_insert_id();
        }
        public function update($params, $where = null) {
            if ($params == null || !is_array($params)) {
                return -1;
            }
            $upvals = $this->_getupdatestring($params);
            $wheres = $this->_getwherestring($where);
            $sql = update .$this->_table. set .$upvals. .$wheres;
            //echo [update].$sql.
;
            $result = @mysql_query($sql);
            if (! $result) {
                return -1;
            }
            return @mysql_affected_rows();
        }
        public function delete($where) {
            $wheres = $this->_getwherestring($where);
            $sql = delete from .$this->_table.$wheres;
            //echo [delete].$sql.
;
            $result = @mysql_query($sql);
            if (! $result) {
                return -1;
            }
            return @mysql_affected_rows();
        }
        protected function _getparamkeystring($params) {
            $keys = array_keys($params);
            return implode(,, $keys);
        }
        protected function _getparamvalstring($params) {
            $vals = array_values($params);
            return '.implode(',', $vals).';
        }
        private function _getupdatestring($params) {
            //echo _getupdatestring;
            $sql = ;
            if (is_array($params)) {
                $sql = $this->_getkeyvalstring($params, ,);
            }
            return $sql;
        }
        private function _getwherestring($params) {
            //echo _getwherestring;
            $sql = ;
            if (is_array($params)) {
                $sql = where ;
                $where = $this->_getkeyvalstring($params, and );
                $sql = $sql.$where;
            }
            return $sql;
        }
        private function _getkeyvalstring($params, $split) {
            $str = ;
            if (is_array($params)) {
                $paramarr = array();
                foreach($params as $key=>$val) {
                    $valstr = $val;
                    if (is_string($val)) {
                        $valstr = '.$val.';
                    }
                    $paramarr[] = $key.=.$valstr;
                }
                $str = $str.implode($split, $paramarr);
            }
            return $str;
        }
        public function release() {
            @mysql_close();
        }
    }
    function t($table) {
        return (new simpledao())->table($table);
    }
?>
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