How to add xml in parent node in php - php

Question

I have 2 xml string, which come from below 2 functions :
1) $accessRequestXML = $accessRequesttXML->asXML();
It products this xml string :
<?xml version="1.0"?>
<AccessRequest>
<AccessLicenseNumber>7D54A69331203795</AccessLicenseNumber>
<UserId>peterfelts</UserId>
<Password>abc123</Password>
<AccessRequest>
2)
$rateRequestXml = $rateRequestXML->asXML();
It products this xml string :
<?xml version="1.0"?>
<RatingServiceSelectionRequest>
<Request>
<RequestAction>Rate</RequestAction>
<RequestOption>Rate</RequestOption>
</Request>
<Shipment>
<Shipper>
<Name>Name</Name>
<ShipperNumber></ShipperNumber>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Corado</City>
<PostalCode>00646</PostalCode>
<CountryCode>PR</CountryCode>
</Address>
</Shipper>
<ShipTo>
<CompanyName>Company Name</CompanyName>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Corado</City>
<PostalCode>00646</PostalCode>
<CountryCode>PR</CountryCode>
</Address>
</ShipTo>
<ShipFrom>
<CompanyName>Company Name</CompanyName>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Boca Raton</City>
<StateProvinceCode>FL</StateProvinceCode>
<PostalCode>33434</PostalCode>
<CountryCode>US</CountryCode>
</Address>
</ShipFrom>
<Service>
<Code>02</Code>
<Description>2nd Day Air</Description>
</Service>
<Package>
<PackagingType>
<Code>02</Code>
<Description>UPS Package</Description>
</PackagingType>
<PackageWeight>
<UnitOfMeasurement>
<Code>LBS</Code>
</UnitOfMeasurement>
<Weight>15.2</Weight>
</PackageWeight>
</Package>
</Shipment>
</RatingServiceSelectionRequest>
I want to add RatingServiceSelectionRequest this node to AccessRequest
I want result like this :
<?xml version="1.0"?>
<AccessRequest>
<AccessLicenseNumber>7D54A69331203795</AccessLicenseNumber>
<UserId>peterfelts</UserId>
<Password>abc123</Password>
<RatingServiceSelectionRequest>
<Request>
<RequestAction>Rate</RequestAction>
<RequestOption>Rate</RequestOption>
</Request>
<Shipment>
<Shipper>
<Name>Name</Name>
<ShipperNumber></ShipperNumber>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Corado</City>
<PostalCode>00646</PostalCode>
<CountryCode>PR</CountryCode>
</Address>
</Shipper>
<ShipTo>
<CompanyName>Company Name</CompanyName>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Corado</City>
<PostalCode>00646</PostalCode>
<CountryCode>PR</CountryCode>
</Address>
</ShipTo>
<ShipFrom>
<CompanyName>Company Name</CompanyName>
<Address>
<AddressLine1>Address Line</AddressLine1>
<City>Boca Raton</City>
<StateProvinceCode>FL</StateProvinceCode>
<PostalCode>33434</PostalCode>
<CountryCode>US</CountryCode>
</Address>
</ShipFrom>
<Service>
<Code>02</Code>
<Description>2nd Day Air</Description>
</Service>
<Package>
<PackagingType>
<Code>02</Code>
<Description>UPS Package</Description>
</PackagingType>
<PackageWeight>
<UnitOfMeasurement>
<Code>LBS</Code>
</UnitOfMeasurement>
<Weight>15.2</Weight>
</PackageWeight>
</Package>
</Shipment>
</RatingServiceSelectionRequest>
</AccessRequest>
Can anyone please help me how can i do this ?

Answer 1

IMHO - the best way to do this is to import the XML into DOM which allows you more flexible ways of adding nodes and moving them around.
This code loads the access request as the start of the DOM document and then imports the second XML as a new node, it then appends it to the end of the existing XML...
$dom = new DOMDocument();
$dom->loadXML($accessRequestXML->asXML());
$importrr = dom_import_simplexml($rateRequestXml);
$domImportRR = $dom->importNode($importrr, true);
$dom->documentElement->appendChild($domImportRR);
echo $dom->saveXML();