php+pdo实现的购物车类完整示例

本文实例讲述了php+pdo实现的购物车类。分享给大家供大家参考，具体如下：<?phpsession_

本文实例讲述了php+pdo实现的购物车类。分享给大家供大家参考，具体如下：

<?php
session_start();
class Cart
{
 public $pdo = null;
 public function __construct($config)
 {
 $host = $config['host'];
 $user = $config['user'];
 $db = $config['db'];
 $pwd = $config['pwd'];
 if (empty($_SESSION['user_id'])) {
 return show(0, '请先登录');
 }
 try {
 $this->pdo = new PDO("mysql:host=$host;dbname=$db", "$user", "$pwd", array(PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION));
 $this->pdo->query("set names utf8");
 } catch (PDOException $e) {
 echo $e->getMessage();
 }
 }
 //添加商品到购物车
 public function add_cart($productid, $num)
 {
 $sql = "select price from shop_product where id=?";
 $stmt = $this->pdo->prepare($sql);
 $stmt->execute(array($productid));
 $data = $stmt->fetch(PDO::FETCH_ASSOC);
 $price = $data['price'];
 $createtime = time();
 $sql = "select * from shop_cart where productid=? and userid=?";
 $stmt = $this->pdo->prepare($sql);
 $stmt->execute(array($productid, $_SESSION['user_id']));
 $data = $stmt->fetch(PDO::FETCH_ASSOC);
 if ($data) {
 $sql = "update shop_cart set num=num+? where userid=? and productid=?";
 $params = array($num, $_SESSION['user_id'], $productid);
 } else {
 $sql = "insert into shop_cart(productid,num,userid,price,createtime) values(?,?,?,?,?)";
 $params = array($productid, $num, $_SESSION['user_id'], $price, $createtime);
 }
 $stmt = $this->pdo->prepare($sql);
 $stmt->execute($params);
 $rows = $stmt->rowCount();
 return $rows ?
 show(1, 'ok', $rows) :
 show(0, 'fail');
 }
 //修改购买数量
 public function change_num($productid, $num)
 {
 $sql = "update shop_cart set num=? where userid=? and productid=?";
 $stmt = $this->pdo->prepare($sql);
 $stmt->execute(array($num, $_SESSION['user_id'], $productid));
 $rows = $stmt->rowCount();
 return $rows ?
 show(1, 'ok', $rows) :
 show(0, 'fail');
 }
 //清空购物车
 public function clear_cart()
 {
 $sql = "delete from shop_cart where userid=?";
 $stmt = $this->pdo->prepare($sql);
 $this->pdo->execute(array($this->user_id));
 $rows = $stmt->rowCount();
 return $rows ?
 show(1, 'ok', $rows) :
 show(0, 'fail');
 }
 //从购物车中删除商品
 public function remove_cart($productid)
 {
 $sql = "delete from shop_cart where productid=? and userid=?";
 $stmt = $this->pdo->prepare($sql);
 $stmt->execute(array($productid, $_SESSION['user_id']));
 $rows = $stmt->rowCount();
 return $rows ?
 show(1, 'ok', $rows) :
 show(0, 'fail');
 }
}
//处理数据
function show($status, $message, $data = array())
{
 $result = array(
 'status' => $status,
 'message' => $message,
 'data' => $data
 );
 exit(json_encode($result));
}
//简单使用
$user = [
 'host' => '',
 'user' => 'root',
 'pwd' => 'root',
 'db' => 'shop',
];
$productid = intval($_POST['productid']);
$num = intval($_POST['num']);
$cart = new Cart($user);
//添加到购物车
$cart->add_cart($productid, $num);
//删除指定的商品
$cart->remove_cart($productid);
//清空
$cart->clear_cart();
?>