如何用PHP开发微信公众号的积分商城

// 首先，获取微信公众号的用户授权
// 在微信公众号菜单或其他场景下，引导用户点击授权按钮跳转到一个授权页面
// 获取用户授权后，微信会回调一个授权码 code 给你的后端
// 根据 code 来获取用户的 OpenID

$code = $_GET['code'];
$apiUrl = "https://api.weixin.qq.com/sns/oauth2/access_token?appid=YourAppID&secret=YourAppSecret&code=".$code."&grant_type=authorization_code";

$result = file_get_contents($apiUrl);
$result = json_decode($result, true);

$openid = $result['openid'];

// 假设数据库连接已经建立并且选中了目标数据库
// 用户表的结构：id, openid, balance
// 积分记录表的结构：id, openid, type, points, created_at

// 获取用户积分余额
$sql = "SELECT balance FROM user WHERE openid = '$openid'";
$result = mysqli_query($conn, $sql);
$row = mysqli_fetch_assoc($result);
$balance = $row['balance'];

// 积分记录
$sql = "INSERT INTO points (openid, type, points, created_at) VALUES ('$openid', '$type', '$points', NOW())";
mysqli_query($conn, $sql);

// 更新用户积分余额
$newBalance = $balance + $points;
$sql = "UPDATE user SET balance = '$newBalance' WHERE openid = '$openid'";
mysqli_query($conn, $sql);

// 假设商品表的结构：id, name, points, image

// 查询商品列表
$sql = "SELECT * FROM goods";
$result = mysqli_query($conn, $sql);

// 显示商品列表
while ($row = mysqli_fetch_assoc($result)) {
    echo "<div>";
    echo "<img class="lazy" data-src='".$row['image']."'>";
    echo "<h3>".$row['name']."</h3>";
    echo "<p>积分：".$row['points']."</p>";
    echo "<button onclick='exchange(".$row['id'].")'>兑换</button>";
    echo "</div>";
}

// 积分兑换
function exchange($id) {
    // 查询商品积分
    $sql = "SELECT points FROM goods WHERE id = '$id'";
    $result = mysqli_query($conn, $sql);
    $row = mysqli_fetch_assoc($result);
    $points = $row['points'];

    // 判断用户积分是否足够
    if ($balance < $points) {
        echo "积分不足，无法兑换";
    } else {
        // 扣除用户积分
        $newBalance = $balance - $points;
        $sql = "UPDATE user SET balance = '$newBalance' WHERE openid = '$openid'";
        mysqli_query($conn, $sql);

        // 记录积分操作
        $sql = "INSERT INTO points (openid, type, points, created_at) VALUES ('$openid', 'exchange', '$points', NOW())";
        mysqli_query($conn, $sql);

        echo "兑换成功";
    }
}

$apiUrl = "https://api.weixin.qq.com/cgi-bin/menu/create?access_token=YourAccessToken";

$data = '{
    "button": [
        {
            "name": "积分商城",
            "type": "view",
            "url": "http://yourdomain.com/mall.php"
        }
    ]
}';

$result = curl_post($apiUrl, $data);