用于结帐/购物篮系统的PHP会话Vairable

<?php
session_start(); // 开始会话

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

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

    if (array_key_exists($product_id, $_SESSION['basket'])) {
        $_SESSION['basket'][$product_id] += $quantity;
    } else {
        $_SESSION['basket'][$product_id] = $quantity;
    }
}

// 显示购物篮内容
echo "<h2>购物篮内容</h2>";
if (isset($_SESSION['basket']) && !empty($_SESSION['basket'])) {
    foreach ($_SESSION['basket'] as $product_id => $quantity) {
        echo "商品ID: $product_id, 数量: $quantity<br>";
    }
} else {
    echo "购物篮为空";
}
?>

<!-- 示例表单 -->
<form method="post">
    商品ID: <input type="text" name="product_id"><br>
    数量: <input type="number" name="quantity"><br>
    <input type="submit" name="add_to_basket" value="添加到购物篮">
</form>