php实现购物车

PHP实现购物车功能

购物车功能是电商网站的核心模块之一，通常涉及商品添加、删除、数量修改和结算等操作。以下是使用PHP实现购物车功能的几种方法。

使用Session存储购物车数据

Session是一种常见的存储购物车数据的方式，适用于小型电商网站或不需要持久化购物车数据的场景。

// 启动Session
session_start();

// 添加商品到购物车
if (isset($_POST['add_to_cart'])) {
    $product_id = $_POST['product_id'];
    $quantity = $_POST['quantity'];

    if (!isset($_SESSION['cart'])) {
        $_SESSION['cart'] = array();
    }

    if (isset($_SESSION['cart'][$product_id])) {
        $_SESSION['cart'][$product_id] += $quantity;
    } else {
        $_SESSION['cart'][$product_id] = $quantity;
    }
}

// 从购物车移除商品
if (isset($_GET['remove'])) {
    $product_id = $_GET['remove'];
    unset($_SESSION['cart'][$product_id]);
}

// 更新购物车商品数量
if (isset($_POST['update_cart'])) {
    foreach ($_POST['quantity'] as $product_id => $quantity) {
        $_SESSION['cart'][$product_id] = $quantity;
    }
}

使用数据库存储购物车数据

对于需要持久化购物车数据的场景，可以将购物车信息存储到数据库中。

// 数据库连接
$db = new PDO('mysql:host=localhost;dbname=ecommerce', 'username', 'password');

// 添加商品到购物车
if (isset($_POST['add_to_cart'])) {
    $user_id = $_SESSION['user_id'];
    $product_id = $_POST['product_id'];
    $quantity = $_POST['quantity'];

    $stmt = $db->prepare("INSERT INTO cart (user_id, product_id, quantity) VALUES (?, ?, ?) ON DUPLICATE KEY UPDATE quantity = quantity + ?");
    $stmt->execute([$user_id, $product_id, $quantity, $quantity]);
}

// 从购物车移除商品
if (isset($_GET['remove'])) {
    $user_id = $_SESSION['user_id'];
    $product_id = $_GET['remove'];

    $stmt = $db->prepare("DELETE FROM cart WHERE user_id = ? AND product_id = ?");
    $stmt->execute([$user_id, $product_id]);
}

// 更新购物车商品数量
if (isset($_POST['update_cart'])) {
    $user_id = $_SESSION['user_id'];

    foreach ($_POST['quantity'] as $product_id => $quantity) {
        $stmt = $db->prepare("UPDATE cart SET quantity = ? WHERE user_id = ? AND product_id = ?");
        $stmt->execute([$quantity, $user_id, $product_id]);
    }
}

购物车页面展示

购物车页面通常需要显示商品列表、数量、单价和总价等信息。

// 获取购物车商品列表
if (isset($_SESSION['cart'])) {
    $cart_items = $_SESSION['cart'];
} else {
    $cart_items = array();
}

// 计算总价
$total = 0;
foreach ($cart_items as $product_id => $quantity) {
    // 假设从数据库获取商品信息
    $stmt = $db->prepare("SELECT price FROM products WHERE id = ?");
    $stmt->execute([$product_id]);
    $product = $stmt->fetch();

    $total += $product['price'] * $quantity;
}

// 显示购物车内容
foreach ($cart_items as $product_id => $quantity) {
    echo "Product ID: $product_id, Quantity: $quantity";
    echo "<a href='cart.php?remove=$product_id'>Remove</a>";
}
echo "Total: $total";

结算功能实现

结算功能通常涉及订单创建和购物车清空。

// 创建订单
if (isset($_POST['checkout'])) {
    $user_id = $_SESSION['user_id'];
    $total = $_POST['total'];

    $stmt = $db->prepare("INSERT INTO orders (user_id, total) VALUES (?, ?)");
    $stmt->execute([$user_id, $total]);
    $order_id = $db->lastInsertId();

    // 添加订单详情
    foreach ($_SESSION['cart'] as $product_id => $quantity) {
        $stmt = $db->prepare("INSERT INTO order_items (order_id, product_id, quantity) VALUES (?, ?, ?)");
        $stmt->execute([$order_id, $product_id, $quantity]);
    }

    // 清空购物车
    unset($_SESSION['cart']);
    echo "Order placed successfully!";
}

购物车功能优化

为提高用户体验，可以添加以下优化功能：

• 异步更新购物车数量（使用AJAX）
• 商品库存检查
• 优惠券和折扣计算
• 多语言支持

// AJAX更新购物车数量示例
if (isset($_POST['ajax_update'])) {
    $product_id = $_POST['product_id'];
    $quantity = $_POST['quantity'];

    $_SESSION['cart'][$product_id] = $quantity;

    // 返回更新后的总价
    $total = 0;
    foreach ($_SESSION['cart'] as $pid => $qty) {
        $stmt = $db->prepare("SELECT price FROM products WHERE id = ?");
        $stmt->execute([$pid]);
        $product = $stmt->fetch();
        $total += $product['price'] * $qty;
    }

    echo json_encode(['total' => $total]);
    exit;
}

以上代码示例展示了PHP实现购物车功能的基本方法，可以根据实际需求进行调整和扩展。