使用單列模式鏈接pdo並操作

<?php

class MyPDO{

private $type; //資料庫類型

private $host; //主機地址

private $port; //埠號

private $dbname; //資料庫名

private $charset; //字元編碼

private $user; //用戶名

private $pwd; //密碼

private $pdo; //pdo對象

private static $instance;

private function __construct($param){

$this->initParam($param);

$this->initPDO();

$this->initException();

}

private function __clone(){

}

//初始化參數

private function initParam($param){

$this->type=isset($param[type])?$param[type]:mysql;

$this->host=isset($param[host])?$param[host]:localhost;

$this->port=isset($param[port])?$param[port]:3306;

$this->dbname=isset($param[dbname])?$param[dbname]:;

$this->charset=isset($param[charset])?$param[charset]:utf8;

$this->user=isset($param[user])?$param[user]:;

$this->pwd=isset($param[pwd])?$param[pwd]:;

}

//連接資料庫

private function initPDO(){

try{

$dsn="{$this->type}:host={$this->host};port={$this->port};dbname={$this->dbname};charset={$this->charset}";

$this->pdo=new PDO($dsn,$this->user,$this->pwd);

}catch(PDOException $ex){

$this->showException($ex);

}

}

//設置異常模式

private function initException(){

$this->pdo->setAttribute(PDO::ATTR_ERRMODE,PDO::ERRMODE_EXCEPTION);

}

//封裝顯示異常信息

private function showException($ex,$sql=){

if($sql!=){

echo SQL語句執行失敗<br>;

echo 錯誤的SQL語句是：.$sql,<br>;

}

echo 錯誤編號：.$ex->getCode(),<br>;

echo 錯誤文件：.$ex->getFile(),<br>;

echo 錯誤行號：.$ex->getLine(),<br>;

echo 錯誤信息：.$ex->getMessage(),<br>;

exit;

}

//執行數據操作語句

public function exec($sql){

try{

return $this->pdo->exec($sql);

} catch (PDOException $ex) {

$this->showException($ex, $sql);

}

}

//獲取插入記錄的自動增長的編號

public function getLastInsertId(){

return $this->pdo->lastInsertId();

}

//封裝匹配的類型

private function fetchType($type){

switch($type){

case assoc:

return PDO::FETCH_ASSOC;

case num:

return PDO::FETCH_NUM;

case both:

return PDO::FETCH_BOTH;

default:

return PDO::FETCH_ASSOC;

}

}

//獲取所有記錄，返回二維數組

public function fetchAll($sql,$type=assoc){

try{

$stmt=$this->pdo->query($sql);

$type= $this->fetchType($type);

return $stmt->fetchAll($type);

} catch (PDOException $ex){

$this->showException($ex, $sql);

}

}

//匹配一行

public function fetchRow($sql,$type=assoc){

try{

$stmt=$this->pdo->query($sql);

$type= $this->fetchType($type);

return $stmt->fetch($type);

}catch(PDOException $ex){

$this->showException($ex, $sql);

}

}

//匹配一行一列

public function fetchColumn($sql){

try{

$stmt=$this->pdo->query($sql);

return $stmt->fetchColumn();

} catch (Exception $ex) {

$this->showException($ex, $sql);

}

}

//獲取單例

public static function getInstance($param=array()){

if(!self::$instance instanceof self)

self::$instance=new self($param);

return self::$instance;

}

}