get the value of an XML attribute using php - php

Question

I am attempting to take a value from an attribute and use it in an array to insert it into a MySQL table. My XML file is:
<?xml version="1.0"?>
<GetMatchingProductForIdResponse xmlns="http://mws.amazonservices.com/schema/Products/2011-10-01">
<GetMatchingProductForIdResult Id="9780596515898" IdType="ISBN" status="Success">
<Products xmlns="http://mws.amazonservices.com/schema/Products/2011-10-01" xmlns:ns2="http://mws.amazonservices.com/schema/Products/2011-10-01/default.xsd">
<Product>
<Identifiers>
<MarketplaceASIN>
<MarketplaceId>ATVPDKIKX0DER</MarketplaceId>
<ASIN>B0026OR39Y</ASIN>
</MarketplaceASIN>
</Identifiers>
and using php I need to extract out the value of Id in GetMatchingProductForIdResult. So far my code is this:
$parsed_xml = ProductId_xml($isbn);
$isbn13 =(string)$parsed_xml->GetMatchingProductProductForIdResult[0]->attributes();
echo $isbn13['Id']; die;
I am getting no result from the echo statement, even if I change it to print_r or var_dump. I have also tried:
$amazonResult = array(
'isbn' => $parsed_xml->GetMatchingProductProductForIdResult[0]['Id'],
Which yielded no results either. I am not sure where to go from here and any assistance will be greatly appreciated.
EDIT: To clarify this a little bit, the value in Id will change for each record. So what is "9780596515898" this time could be Id="9780596312674" for the next record. I need to know what each one is so I can insert them into the database with the other information I need.

Answer 1

I can access the attributes if I close out the XML - otherwise all it does is throw errors.
You can access all attributes, or individually through simplexml:
$str = <<<XML
<?xml version="1.0"?>
<GetMatchingProductForIdResponse xmlns="http://mws.amazonservices.com/schema/Products/2011-10-01">
<GetMatchingProductForIdResult Id="9780596515898" IdType="ISBN" status="Success">
<Products xmlns="http://mws.amazonservices.com/schema/Products/2011-10-01" xmlns:ns2="http://mws.amazonservices.com/schema/Products/2011-10-01/default.xsd">
<Product>
<Identifiers>
<MarketplaceASIN>
<MarketplaceId>ATVPDKIKX0DER</MarketplaceId>
<ASIN>B0026OR39Y</ASIN>
</MarketplaceASIN>
</Identifiers>
</Product>
</Products>
</GetMatchingProductForIdResult>
</GetMatchingProductForIdResponse>
XML;
$xml = simplexml_load_string($str);
foreach($xml->GetMatchingProductForIdResult->attributes() as $a => $b) {
echo $a,'="',$b,"\"\n";
}
// Or access them directly:
echo $xml->GetMatchingProductForIdResult->attributes()->Id;
Outputs:
Id="9780596515898" IdType="ISBN" status="Success" 9780596515898