public function addPostFields(array $formParams, array &$multipart, $arrayName = '') { foreach ($formParams as $name => $value) { if (!empty($arrayName)) { $name = $arrayName . '[' . $name . ']'; } if (is_array($value)) { $this->addPostFields($value, $multipart, $name); } else { $multipart[] = ['name' => $name, 'contents' => $value]; } } }