PHP商城开发技巧：设计评分和评论管理功能

<div class="rating">
    <?php
    $productId = $_GET['product_id']; // 通过URL参数获取商品ID
    // 查询评分表格中对应商品ID的所有评分
    $query = "SELECT rating FROM ratings WHERE product_id = $productId";
    $result = mysqli_query($connection, $query);
    
    $totalRatings = mysqli_num_rows($result); // 获取评分总数
    $averageRating = 0;
    while ($row = mysqli_fetch_assoc($result)) {
        // 计算所有评分的平均值
        $averageRating += $row['rating'];
    }
    $averageRating = $averageRating / $totalRatings;
    ?>
    <h3>商品评分：<?php echo $averageRating; ?></h3>
    <p>评分人数：<?php echo $totalRatings; ?></p>
</div>

<div class="comments">
    <?php
    // 查询评论表格中对应商品ID的所有评论
    $query = "SELECT comment FROM comments WHERE product_id = $productId";
    $result = mysqli_query($connection, $query);
    
    while ($row = mysqli_fetch_assoc($result)) {
        // 显示每条评论
        echo "<p>" . $row['comment'] . "</p>";
    }
    ?>
</div>

$productId = $_POST['product_id']; // 通过表单提交获取商品ID
$userId = $_SESSION['user_id']; // 获取当前用户的ID
$rating = $_POST['rating']; // 获取用户提交的评分分数

$query = "INSERT INTO ratings (product_id, user_id, rating) VALUES ($productId, $userId, $rating)";
mysqli_query($connection, $query);

$productId = $_POST['product_id']; // 通过表单提交获取商品ID
$userId = $_SESSION['user_id']; // 获取当前用户的ID
$comment = $_POST['comment']; // 获取用户提交的评论内容

$query = "INSERT INTO comments (product_id, user_id, comment) VALUES ($productId, $userId, '$comment')";
mysqli_query($connection, $query);