关联数组和绑定参数

$array = array(
    "name" => "John",
    "age" => 30,
    "city" => "New York"
);

echo $array["name"]; // 输出 "John"
echo $array["age"]; // 输出 30
echo $array["city"]; // 输出 "New York"

// 使用 PDO 绑定参数
$stmt = $pdo->prepare("SELECT * FROM users WHERE name = :name");
$stmt->bindParam(":name", $name);
$name = "John";
$stmt->execute();

// 使用 MySQLi 绑定参数
$stmt = $mysqli->prepare("SELECT * FROM users WHERE name = ?");
$stmt->bind_param("s", $name);
$name = "John";
$stmt->execute();