跨平台 PHP 数据库连接：Windows、Linux 和 macOS

<?php
// 连接到 MySQL 数据库
$dsn = 'mysql:host=localhost;dbname=mydb;charset=utf8';
$user = 'username';
$password = 'password';

try {
    // 创建一个 PDO 实例
    $pdo = new PDO($dsn, $user, $password);
    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

    // 执行查询
    $statement = $pdo->prepare("SELECT * FROM users");
    $statement->execute();

    // 获取结果集
    $users = $statement->fetchAll(PDO::FETCH_ASSOC);

    // 循环结果集
    foreach ($users as $user) {
        echo $user['name'] . "\n";
    }
} catch (PDOException $e) {
    // 处理错误
    echo "Error: " . $e->getMessage();
}
?>

<?php
// 连接到 MySQL 数据库
$mysqli = new mysqli("localhost", "username", "password", "mydb");

// 检查连接
if ($mysqli->connect_error) {
    echo "Connect failed: " . $mysqli->connect_error;
    exit;
}

// 执行查询
$result = $mysqli->query("SELECT * FROM users");

// 获取结果集
while ($row = $result->fetch_assoc()) {
    echo $row['name'] . "\n";
}

// 关闭连接
$mysqli->close();
?>

<?php
// 获取平台类型
$platform = strtoupper(substr(PHP_OS, 0, 3));

// 加载特定平台的连接逻辑
switch ($platform) {
    case 'WIN':
        require_once 'connect_mysql.php';
        break;
    case 'LIN':
        require_once 'connect_pgsql.php';
        break;
    case 'MAC':
        require_once 'connect_sqlite.php';
        break;
    default:
        echo 'Unsupported platform';
        exit;
}

// 执行数据库操作...
?>