<?php
header("content-type:text/html;charset=utf-8");
//封装一个类：完成一个new 就可以操作数据库相应操作
class myPDO{
//定义属性，接受实例化时候传入的数据库信息
private $type;
private $host;
private $port;
private $dbname;
private $charset;
private $user;
private $pass;
//pdo属性：将局部变量转换为全局变量
private $pdo;
//定义属性，存储一数组属性$args来帮助预处理判断某一个预处理是否已经操作过
private $args=array();
//构造方法
public function __construct($info=array()){
$this->type = isset($info['type'])?$info['type']:strtolower('mysql');
$this->host = isset($info['host'])?$info['host']:'host';
$this->port = isset($info['port'])?$info['port']:'3306';
$this->dbname = isset($info['dbname '])?$info['dbname ']:'php0810';
$this->charset = isset($info['charset '])?$info['charset ']:'utf8';
$this->user = isset($info['user'])?$info['user']:'root';
$this->pass = isset($info['pass'])?$info['pass']:'1234';
//自动连接：当类实例化时自动连接
$this->db_connect();
}
//数据库连接方法
public function db_connect(){
$dsn = "{$this->type}:{$this->host};port={$this->port};charset={$this->charset};dbname={$this->dbname}";
try{
//连接认证
$this->pdo = new PDO($dsn,$this->user,$this->pass);
//修改PDO::FETCH()属性，获取数据为关联数据
$this->pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE,PDO::FETCH_ASSOC);
}catch(PDOException $e){
echo "链接失败！".'<br/>';
echo "错误代码：".$e->getCode().'<br/>';
echo "错误文件：".$e->getFile().'<br/>';
echo "错误行：".$e->getLine().'<br/>';
echo "错误信息：".$e->getMessage().'<br/>';
exit;
}
}
//增删改操作：返回影响行或者自增长ID
public function db_exec($sql){
$res = $this->pdo->exec($sql);
//判断
$this->db_error($res);
}
//查找操作：查找一行数据
public function db_getOne($sql){
$stmt = $this->pdo->query($sql);
$this->db_error($stmt);
return $res = $stmt->fetch();
}
//查找很多数据
public function db_getAll($sql){
$stmt = $this->pdo->query($sql);
$this->db_error($stmt);
return $res = $stmt->fetchAll();
}
//验证方法
public function db_error($sql){
if($sql ===false){
echo "SQL语法错误！".'<br/>';
echo "错误编码：".$this->pdo->errorCode().'<br/>';
echo "错误信息：".$this->pdo->errorInfo()[2].'<br/>';
exit;
}
return $sql;
}
//预处理操作：能够实现，
public function db_prepare($sql,$args){
//判断此$sql是否已经产生过预处理
//执行SQL，完成预处理
if(!in_array($sql,$this->args)){
$this->args[$sql] = $sql;
$stmt = $this->pdo->prepare($sql); //执行与操作
}
//执行execute操作
$stmt ->execute($args);
$row = $stmt->fetch();
return $row;
}
}
//测试
$m = new myPDO();
//var_dump($m);
//$res = $m->db_exec("update class set classname='PHP0120' where id=1");
//var_dump($res);
//$res = $m->db_getOne("select * from class where id=1");
//$res = $m->db_getAll("select * from my_goods");
$res = $m->db_prepare("select * from class where id=?",array(2));
var_dump($res);
