PHP操作Mysql（CRUD）增、删、改、查类
<?php/** * 数据库操作基类 * @author yanli_xu@163.com * */class DB {/** * 执行插入操作的方法 * @param $table : 表名 * @param $values : 数组数据 */function insert($table, $values) {$sql = "INSERT INTO {$table}";$keysql = '';$valuesql = '';foreach ( $values as $k => $v ) {$keysql .= "{$k},";if (preg_match ( "/^[0-9]+$/", $v )) {$valuesql .= "{$v},";} else {$valuesql .= "'{$v}',";}}$sql = $sql . '(' . substr ( $keysql, 0, - 1 ) . ')VALUES(' . substr ( $valuesql, 0, - 1 ) . ')';return $this->query ( $sql );}/** * 执行删除操作的方法 * @param $table : 表名 * @param $where : 删除条件 */function delete($table, $where = '') {$sql = "DELETE FROM {$table}";if ($where != '')$sql .= " WHERE {$where}";return $this->query ( $sql );}/** * 执行更新操作的方法 * @param $table : 表名 * @param $values : 数组数据 * @param $where ： 更新条件 */function update($table, $values, $where) {$sql = "UPDATE {$table} SET ";foreach ( $values as $k => $v ) {if (preg_match ( "/^[0-9]+$/", $v )) {$sql .= "$k={$v},";} else {$sql .= "$k='{$v}',";}}$sql = substr ( $sql, 0, - 1 );$sql .= " WHERE {$where}";return $this->query ( $sql );}/** * 执行查询操作 * @param $what : 查询字段 * @param $table : 目的表 * @param $where : 查询条件 * @param $orderby : 查询排序 * @param $limit : 查询数量 */function select($what, $table, $where = '', $orderby = '', $limit = '') {$sql = "SELECT {$what} FROM {$table}";if ($where != '')$sql .= " WHERE {$where}";if ($orderby != '')$sql .= " ORDER BY {$orderby}";if ($limit != '')$sql .= " LIMIT {$limit}";return $this->fetch_array ( $this->query ( $sql ) );}function query($sql) {$this->_query ( $sql );}function fetch_array() {return $this->_fetch_array ();}function num_rows() {return $this->_num_rows ();}function close() {$this->_close ();}}?>??
<?phpclass Mysql extends DB {var $link_id;var $result;function Mysql() {$conn = mysql_connect ( SERVER, USERNAME, PASSWORD ) or die ( "连接失败" );mysql_select_db ( DATABASE_NAME, $conn );mysql_query ( "SET NAMES 'gbk'", $conn );$this->link_id = $conn;}function query($sql) {return $this->result = mysql_query ( $sql, $this->link_id );}function _fetch_array() {$data = array ();while ( $row = mysql_fetch_array ( $this->result ) ) {array_push ( $data, $row );}$this->close ();return $data;}function _num_rows() {return mysql_num_rows ( $this->result );}function _close() {//mysql_free_result ( $this->result );//mysql_close ( $this->link_id );}}?>?