PHP学习笔记：电子商务与在线交易

<?php
// 连接数据库
$link = Mysqli_connect("localhost", "username", "passWord", "database");

// 查询商品信息
$sql = "SELECT * FROM products";
$result = mysqli_query($link, $sql);
while ($row = mysqli_fetch_assoc($result)) {
    echo "商品名称：" . $row['name'] . "<br>";
    echo "商品价格：" . $row['price'] . "<br>";
    echo "<br>";
}

// 插入用户信息
$name = "张三";
$email = "zhangsan@example.com";
$sql = "INSERT INTO users (name, email) VALUES ('$name', '$email')";
mysqli_query($link, $sql);

// 断开数据库连接
mysqli_close($link);
?>

<?php
session_start();

// 用户登录验证
if ($_POST['username'] == 'admin' && $_POST['password'] == '123456') {
    $_SESSION['loggedIn'] = true;
    echo "登录成功！";
} else {
    echo "用户名或密码错误！";
}

// 用户注销
if (isset($_GET['loGout'])) {
    session_destroy();
    echo "注销成功！";
}
?>

<?php
// 支付宝支付接口
$gateway = "https://openapi.alipay.com/gateway.do";
$appId = "..."; // 应用ID
$charset = "UTF-8";
$signType = "RSA2";
$returnUrl = "..."; // 支付成功后跳转的页面
$notifyUrl = "..."; // 支付成功后异步通知的接口

// 构造支付参数
$params = array(
    'app_id' => $appId,
    'method' => 'alipay.trade.page.pay',
    'charset' => $charset,
    'sign_type' => $signType,
    'return_url' => $returnUrl,
    'notify_url' => $notifyUrl,
    // 其他参数...
);

// 生成签名
ksort($params);
$paramStr = '';
foreach ($params as $key => $value) {
    $paramStr .= $key . '=' . $value . '&';
}
$paramStr = rtrim($paramStr, '&');
$sign = openssl_sign($paramStr, $sign, openssl_pkey_get_private('private_key.pem'), OPENSSL_ALGO_SHA256);
$sign = base64_encode($sign);

// 跳转到支付页面
$redirectUrl = $gateway . '?' . $paramStr . '&sign=' . urlencode($sign);
header("Location: $redirectUrl");
?>