azure-storage-common/src/Common/Internal/Serialization/XmlSerializer.php
private function arr2xml(\XMLWriter $xmlw, array $data, $defaultTag = null)
    {
        foreach ($data as $key => $value) {
            if ($key === Resources::XTAG_ATTRIBUTES) {
                foreach ($value as $attributeName => $attributeValue) {
                    $xmlw->writeAttribute($attributeName, $attributeValue);
                }
            } elseif (is_array($value)) {
                if (!is_int($key)) {
                    if ($key != Resources::EMPTY_STRING) {
                        $xmlw->startElement($key);
                    } else {
                        $xmlw->startElement($defaultTag);
                    }
                }

                $this->arr2xml($xmlw, $value);

                if (!is_int($key)) {
                    $xmlw->endElement();
                }
            } else {
                $xmlw->writeElement($key, $value);
            }
        }
    }
private function arr2xml(\XMLWriter $xmlw, array $data, $defaultTag = null)
    {
        foreach ($data as $key => $value) {
            if ($key === Resources::XTAG_ATTRIBUTES) {
                foreach ($value as $attributeName => $attributeValue) {
                    $xmlw->writeAttribute($attributeName, $attributeValue);
                }
            } elseif (is_array($value)) {
                if (!is_int($key)) {
                    if ($key != Resources::EMPTY_STRING) {
                        $xmlw->startElement($key);
                    } else {
                        $xmlw->startElement($defaultTag);
                    }
                }

                $this->arr2xml($xmlw, $value);

                if (!is_int($key)) {
                    $xmlw->endElement();
                }
            } else {
                $xmlw->writeElement($key, $value);
            }
        }
    }
Takes an array and produces XML based on it.

@param XMLWriter $xmlw       XMLWriter object that was previously instanted
and is used for creating the XML.
@param array     $data       Array to be converted to XML.
@param string    $defaultTag Default XML tag to be used if none specified.

@return void