在PHP MySQL PDO中有没有办法通过表名来索引数组呢？

<?php
// 连接数据库
$dsn = 'mysql:host=localhost;dbname=test;charset=utf8';
$username = 'username';
$password = 'password';
$options = [
    PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
    PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
];
$pdo = new PDO($dsn, $username, $password, $options);

// 获取表的结构信息
$tableName = 'your_table_name';
$sql = "DESCRIBE $tableName";
$stmt = $pdo->query($sql);
$tableStructure = $stmt->fetchAll();

// 构建关联数组
$tableArray = [];
foreach ($tableStructure as $column) {
    $columnName = $column['Field'];
    $tableArray[$columnName] = null; // 设置默认值为null
}

// 使用表名作为索引
var_dump($tableArray[$tableName]);
?>