PHP多维数组搜索的返回键

function searchKey($array, $searchKey) {
    foreach ($array as $key => $value) {
        if ($key === $searchKey) {
            return $key;
        }
        if (is_array($value)) {
            $result = searchKey($value, $searchKey);
            if ($result !== false) {
                return $result;
            }
        }
    }
    return false;
}

// 示例多维数组
$array = array(
    'key1' => 'value1',
    'key2' => array(
        'key3' => 'value3',
        'key4' => array(
            'key5' => 'value5',
            'key6' => 'value6'
        )
    )
);

$searchKey = 'key5';
$result = searchKey($array, $searchKey);

if ($result !== false) {
    echo "找到了键 '{$searchKey}'";
} else {
    echo "未找到键 '{$searchKey}'";
}