帮我写一个php购物车网页设计代码

好的，以下是一个简单的 PHP 购物车网页设计代码：

<?php
// 连接数据库
$servername = "localhost";
$username = "username";
$password = "password";
$dbname = "myDB";

$conn = new mysqli($servername, $username, $password, $dbname);

// 检查连接是否成功
if ($conn->connect_error) {
    die("Connection failed: " . $conn->connect_error);
}

// 检索商品信息
$sql = "SELECT id, name, price, image FROM products";
$result = $conn->query($sql);

// 开始 HTML 输出
echo "<table>";
echo "<tr><th>Name</th><th>Price</th><th>Image</th><th>Action</th></tr>";

// 输出商品信息
while($row = $result->fetch_assoc()) {
    echo "<tr>";
    echo "<td>" . $row["name"] . "</td>";
    echo "<td>" . $row["price"] . "</td>";
    echo "<td><img src='" . $row["image"] . "'></td>";
    echo "<td><button onclick='addToCart(" . $row["id"] . ")'>Add to Cart</button></td>";
    echo "</tr>";
}

echo "</table>";

// 关闭数据库连接
$conn->close();
?>

<script>
// 添加商品到购物车
function addToCart(id) {
    var cart = JSON.parse(getCookie("cart") || "[]");
    var item = cart.find(function(item) { return item.id === id });
    if (item) {
        item.quantity += 1;
    } else {
        cart.push({ id: id, quantity: 1 });
    }
    setCookie("cart", JSON.stringify(cart), 365);
}

// 获取 Cookie 值
function getCookie(name) {
    var value = "; " + document.cookie;
    var parts = value.split("; " + name + "=");
    if (parts.length == 2) return parts.pop().split(";").shift();
}

// 设置 Cookie 值
function setCookie(name, value, days) {
    var expires = "";
    if (days) {
        var date = new Date();
        date.setTime(date.getTime() + (days * 24 * 60 * 60 * 1000));
        expires = "; expires=" + date.toUTCString();
    }
    document.cookie = name + "=" + (value || "")  + expires + "; path=/";
}
</script>

<?php
// 检查购物车信息并计算总价
$cart = json_decode($_COOKIE["cart"] ?? "[]", true);
$total = 0;
foreach ($cart as $item) {
    $sql = "SELECT price FROM products WHERE id = " . $item["id"];
    $result = $conn->query($sql);
    if ($result->num_rows > 0) {
        $row = $result->fetch_assoc();
        $total += $row["price"] * $item["quantity"];
    }
}

// 输出购物车信息
echo "<p>Items in cart: " . count($cart) . "</p>";
echo "<p>Total: $" . $total . "</p>";
?>

<button onclick="location.href='checkout.php'">Checkout</button>

这个代码包括了连接数据库、检索商品信息、输出商品列表、添加商品到购物车、获取 Cookie、设置 Cookie、计算总价、输出购物车信息和结账按钮等功能。你可以根据你的具体需求进行修改和定制。