PHP 封装POD 类

//1.造DSN：驱动名:dbname=数据库名;host=服务器地址
$dsn = "mysql:dbname=mydb;host=localhost";
//2.造PDO对象
$pdo = new PDO($dsn,"root","123");
//3.写SQL语句
$sql = "select * from Info";
//4.执行SQL语句
//$v = $pdo->query($sql);

//预处理，先把SQL语句放到服务器上等待我们给他指令去执行
//准备一条SQL语句
$stm = $pdo->prepare($sql);

//执行准备好的SQL语句,成功返回true，失败返回false
if($stm->execute())
{
//1.逐行取数据
var_dump($stm->fetch());
//2.取所有的
var_dump($stm->fetchAll(PDO::FETCH_OBJ));
//3.取某一列
var_dump($stm->fetchColumn(1));
//4.返回对象
var_dump($stm->fetchObject());

}
else
{
echo "执行失败！";
}

public function PDO($sql,$type=0,$db="mydb",$qd="mysql")   //建一个PDO的方法
{
$dsn = "{$qd}:dbname={$db};host={$this->host}";  //造DSN
$dbconnect = new PDO($dsn,$this->uid,$this->pwd);   //造一个PDO的对象
$stm = $dbconnect->prepare($sql);    //预处理
if($stm->execute())    //执行SQL语句，成功返回true，失败返回false
{
if($type==0)     //0代表查询，返回一个二维数组
{
return $stm->fetchAll();
}
else       //1代表增删改，返回true或flase
{
return $stm->execute();
}
}
else
{
echo "失败！";
}
}