unable to assign a SimpleXmlelementObject to a variable [duplicate]

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• Get value from SimpleXMLElement Object 6 answers

I have an array I create off API return. The return looks like this:

 SimpleXMLElement Object
 (
[Items] => SimpleXMLElement Object
    (
        [Item] => SimpleXMLElement Object
            (
                [ItemId] => 9780136035480
                [DetailURLPage] => http://ift.tt/1te6G96
                [AddToCartButton] => http://ift.tt/1rCXLRR
                [ItemAttributes] => SimpleXMLElement Object
                    (
                        [Title] => Nursing Basics for Clinical Practice [With Access Code]
                        [ISBN10] => 0136035485
                        [ISBN13] => 9780136035480
                    )

                [OfferSummary] => SimpleXMLElement Object
                    (
                        [LowestNewPrice] => $0.00
                        [LowestUsedPrice] => $11.48
                        [TotalNew] => 0
                        [TotalUsed] => 1
                    )

            )

    )

 )

I create an array of variables from the object as below:

 $itemID = $xml->Items->Item->ItemId;
 $title = $xml->Items->Item->ItemAttributes->Title;
 $isbn10 = $xml->Items->Item->ItemAttributes->ISBN10;
 $isbn13 = $xml->Items->Item->ItemAttributes->ISBN13;
 $buyurl= $xml->Items->Item->AddToCartButton;

Not sure why, but everything outputs great except for the $buyurl. When I use print_r on the array with the variables, I get this output:

 Array
 (
     [0] => Array
         (
             [channel] => blah.com
             [buyurl] => SimpleXMLElement Object
                 (
                     [0] => http://ift.tt/1rCXLRW
                 )

             [price] => 11.48
             [condition] => used
             [shipping] => 0
         )

 )

For some reason, I cannot seem to get rid of the buyurl object and simply get the buyurl into a regular key -> value relationship. Any ideas are sure appreciated!