本文实例讲述了PHP的PDO常用类库。分享给大家供大家参考，具体如下：
1、Db.class.php 连接数据库
<?php// 连接数据库class Db { static public function getDB() { try { $pdo = new PDO(DB_DSN, DB_USER, DB_PWD); $pdo->setAttribute(PDO::ATTR_PERSISTENT, true); // 设置数据库连接为持久连接 $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION); // 设置抛出错误 $pdo->setAttribute(PDO::ATTR_ORACLE_NULLS, true); // 设置当字符串为空转换为 SQL 的 NULL $pdo->query('SET NAMES utf8'); // 设置数据库编码 } catch (PDOException $e) { exit('数据库连接错误，错误信息：'. $e->getMessage()); } return $pdo; }}?> 2、Model.class.php 数据库操作类
<?php/*** 数据库操作类库* author Lee.* Last modify $Date: 2012-1-19 13:59；04 $*/class M { private $_db; //数据库句柄 public $_sql; //SQL语句 /** * 构造方法 */ public function __construct() { $this->_db = Db::getDB(); } /** * 数据库添加操作 * @param string $tName 表名 * @param array $field 字段数组 * @param array $val 值数组 * @param bool $is_lastInsertId 是否返回添加ID * @return int 默认返回成功与否，$is_lastInsertId 为true，返回添加ID */ public function insert($tName, $fields, $vals, $is_lastInsertId=FALSE) { try { if (!is_array($fields) || !is_array($vals)) exit($this->getError(__FUNCTION__, __LINE__)); $fields = $this->formatArr($fields); $vals = $this->formatArr($vals, false); $tName = $this->formatTabName($tName); $this->_sql = "INSERT INTO {$tName} ({$fields}) VALUES ({$vals})"; if (!$is_lastInsertId) { $row = $this->_db->exec($this->_sql); return $row; } else { $this->_db->exec($this->_sql); $lastId = (int)$this->_db->lastInsertId(); return $lastId; } } catch (PDOException $e) { exit($e->getMessage()); } } /** * 数据库修改操作 * @param string $tName 表名 * @param array $field 字段数组 * @param array $val 值数组 * @param string $condition 条件 * @return int 受影响的行数 */ public function update($tName, $fieldVal, $condition) { try { if (!is_array($fieldVal) || !is_string($tName) || !is_string($condition)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $upStr = ''; foreach ($fieldVal as $k=>$v) { $upStr .= '`'.$k . '`=' . '/'' . $v . '/'' . ','; } $upStr = rtrim($upStr, ','); $this->_sql = "UPDATE {$tName} SET {$upStr} WHERE {$condition}"; $row = $this->_db->exec($this->_sql); return $row; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 数据库删除操作（注：必须添加 where 条件） * @param string $tName 表名 * @param string $condition 条件 * @return int 受影响的行数 */ public function del($tName, $condition) { try { if (!is_string($tName) || !is_string($condition)) exit($this->getError(__FUNCTION__, __LINE__)); $tName= $this->formatTabName($tName); $this->_sql = "DELETE FROM {$tName} WHERE {$condition}"; $row = $this->_db->exec($this->_sql); return $row; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 返回表总个数 * @param string $tName 表名 * @param string $condition 条件 * @return int */ public function total($tName, $condition='') { try { if (!is_string($tName)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $this->_sql = "SELECT COUNT(*) AS total FROM {$tName}" . ($condition=='' ? '' : ' WHERE ' . $condition); $re = $this->_db->query($this->_sql); foreach ($re as $v) { $total = $v['total']; } return (int)$total; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 数据库删除多条数据 * @param string $tName 表名 * @param string $field 依赖字段 * @param array $ids 删除数组 * @return int 受影响的行数 */ public function delMulti($tName, $field, $ids) { try { if (!is_string($tName) || !is_array($ids)) exit($this->getError(__FUNCTION__, __LINE__)); $delStr = ''; $tName = $this->formatTabName($tName); $field = $this->formatTabName($field); foreach ($ids as $v) { $delStr .= $v . ','; } $delStr = rtrim($delStr, ','); $this->_sql = "DELETE FROM {$tName} WHERE {$field} IN ({$delStr})"; $row = $this->_db->exec($this->_sql); return $row; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 获取表格的最后主键（注：针对 INT 类型） * @param string $tName 表名 * @return int */ public function insertId($tName) { try { if (!is_string($tName)) exit($this->getError(__FUNCTION__, __LINE__)); $this->_sql = "SHOW TABLE STATUS LIKE '{$tName}'"; $result = $this->_db->query($this->_sql); $insert_id = 0; foreach ($result as $v) { $insert_id = $v['Auto_increment']; } return (int)$insert_id; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 检查数据是否已经存在（依赖条件） * @param string $tName 表名 * @param string $field 依赖的字段 * @return bool */ public function exists($tName, $condition) { try { if (!is_string($tName) || !is_string($condition)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $this->_sql = "SELECT COUNT(*) AS total FROM {$tName} WHERE {$condition}"; $result = $this->_db->query($this->_sql); foreach ($result as $v) { $b = $v['total']; } if ($b) { return true; } else { return false; } } catch (PDOException $e) { exit($e->getMessage()); } } /** * 检查数据是否已经存在（依赖 INT 主键） * @param string $tName 表名 * @param string $primary 主键 * @param int $id 主键值 * @return bool */ public function existsByPK($tName, $primary, $id) { try { if (!is_string($tName) || !is_string($primary) || !is_int($id)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $this->_sql = "SELECT COUNT(*) AS total FROM {$tName} WHERE {$primary} = ". $id; $result = $this->_db->query($this->_sql); foreach ($result as $v) { $b = $v['total']; } if ($b) { return true; } else { return false; } } catch (PDOException $e) { exit($e->getMessage()); } } /** * 预处理删除（注：针对主键为 INT 类型，推荐使用） * @param string $tName 表名 * @param string $primary 主键字段 * @param int or array or string $ids 如果是删除一条为 INT，多条为 array，删除一个范围为 string * @return int 返回受影响的行数 */ public function delByPK($tName, $primary, $ids, $mult=FALSE) { try { if (!is_string($tName) || !is_string($primary) || (!is_int($ids) && !is_array($ids) && !is_string($ids)) || !is_bool($mult)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $stmt = $this->_db->prepare("DELETE FROM {$tName} WHERE {$primary}=?"); if (!$mult) { $stmt->bindParam(1, $ids); $row = $stmt->execute(); } else { if (is_array($ids)) { $row = 0; foreach ($ids as $v) { $stmt->bindParam(1, $v); if ($stmt->execute()) { $row++; } } } elseif (is_string($ids)) { if (!strpos($ids, '-')) exit($this->getError(__FUNCTION__, __LINE__)); $split = explode('-', $ids); if (count($split)!=2 || $split[0]>$split[1]) exit($this->getError(__FUNCTION__, __LINE__)); $i = null; $count = $split[1]-$split[0]+1; for ($i=0; $i<$count; $i++) { $idArr[$i] = $split[0]++; } $idStr = ''; foreach ($idArr as $id) { $idStr .= $id . ','; } $idStr = rtrim($idStr, ','); $this->_sql ="DELETE FROM {$tName} WHERE {$primary} in ({$idStr})"; $row = $this->_db->exec($this->_sql); } } return $row; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 返回单个字段数据或单条记录 * @param string $tName 表名 * @param string $condition 条件 * @param string or array $fields 返回的字段，默认是* * @return string || array */ public function getRow($tName, $condition='', $fields="*") { try { if (!is_string($tName) || !is_string($condition) || !is_string($fields) || empty($fields)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $this->_sql = "SELECT {$fields} FROM {$tName} "; $this->_sql .= ($condition=='' ? '' : "WHERE {$condition}") . " LIMIT 1"; $sth = $this->_db->prepare($this->_sql); $sth->execute(); $result = $sth->fetch(PDO::FETCH_ASSOC); if ($fields === '*') { return $result; } else { return $result[$fields]; } } catch (PDOException $e) { exit($e->getMessage()); } } /** * 返回多条数据 * @param string $tName 表名 * @param string $fields 返回字段，默认为* * @param string $condition 条件 * @param string $order 排序 * @param string $limit 显示个数 * @return PDOStatement */ public function getAll($tName, $fields='*', $condition='', $order='', $limit='') { try { if (!is_string($tName) || !is_string($fields) || !is_string($condition) || !is_string($order) || !is_string($limit)) exit($this->getError(__FUNCTION__, __LINE__)); $tName = $this->formatTabName($tName); $fields = ($fields=='*' || $fields=='') ? '*' : $fields; $condition = $condition=='' ? '' : " WHERE ". $condition ; $order = $order=='' ? '' : " ORDER BY ". $order; $limit = $limit=='' ? '' : " LIMIT ". $limit; $this->_sql = "SELECT {$fields} FROM {$tName} {$condition} {$order} {$limit}"; $sth = $this->_db->prepare($this->_sql); $sth->execute(); $result = $sth->fetchAll(PDO::FETCH_ASSOC); return $result; } catch (PDOException $e) { exit($e->getMessage()); } } /** * 格式化数组（表结构和值） * @param array $field * @param bool $isField * @return string */ private function formatArr($field, $isField=TRUE) { if (!is_array($field)) exit($this->getError(__FUNCTION__, __LINE__)); $fields = ''; if ($isField) { foreach ($field as $v) { $fields .= '`'.$v.'`,'; } } else { foreach ($field as $v) { $fields .= '/''.$v.'/''.','; } } $fields = rtrim($fields, ','); return $fields; } /** * 格式化问号 * @param int $count 数量 * @return string 返回格式化后的字符串 */ private function formatMark($count) { $str = ''; if (!is_int($count)) exit($this->getError(__FUNCTION__, __LINE__)); if ($count==1) return '?'; for ($i=0; $i<$count; $i++) { $str .= '?,'; } return rtrim($str, ','); } /** * 错误提示 * @param string $fun * @return string */ private function getError($fun, $line) { return __CLASS__ . '->' . $fun . '() line<font color="red">'. $line .'</font> ERROR!'; } /** * 处理表名 * @param string $tName * @return string */ private function formatTabName($tName) { return '`' . trim($tName, '`') . '`'; } /** * 析构方法 */ public function __destruct() { $this->_db = null; }} 
