如何在循环中生成多级关联数组

function generateMultiLevelArray($data) {
    $result = array();

    foreach ($data as $index => $value) {
        $level1 = array(
            'key1' => $index,
            'key2' => $value
        );

        foreach ($value as $subIndex => $subValue) {
            $level2 = array(
                'subKey1' => $subIndex,
                'subKey2' => $subValue
            );

            foreach ($subValue as $subSubIndex => $subSubValue) {
                $level3 = array(
                    'subSubKey1' => $subSubIndex,
                    'subSubKey2' => $subSubValue
                );

                // 将第三级关联数组作为值赋给第二级关联数组
                $level2[$subSubIndex] = $level3;
            }

            // 将第二级关联数组作为值赋给第一级关联数组
            $level1[$subIndex] = $level2;
        }

        // 将第一级关联数组添加到最终结果数组中
        $result[$index] = $level1;
    }

    return $result;
}

// 示例数据
$data = array(
    'index1' => array(
        'subIndex1' => array(
            'subSubIndex1' => 'value1',
            'subSubIndex2' => 'value2'
        ),
        'subIndex2' => array(
            'subSubIndex3' => 'value3',
            'subSubIndex4' => 'value4'
        )
    ),
    'index2' => array(
        'subIndex3' => array(
            'subSubIndex5' => 'value5',
            'subSubIndex6' => 'value6'
        ),
        'subIndex4' => array(
            'subSubIndex7' => 'value7',
            'subSubIndex8' => 'value8'
        )
    )
);

$result = generateMultiLevelArray($data);
print_r($result);