多个foreach嵌套循环的有关问题

多个foreach嵌套循环的问题


$xml = simplexml_load_file($xml_uri);

$offer_url=array(
					"ItemCondition"					=>"Qualifiers->ItemCondition",
					"ItemSubcondition"				=>"Qualifiers->ItemSubcondition",
					"FulfillmentChannel"			=>"Qualifiers->FulfillmentChannel",
					"ShipsDomestically"				=>"Qualifiers->ShipsDomestically",
					"ShippingTime"					=>"Qualifiers->ShippingTime->Max",
					"SellerPositiveFeedbackRating"	=>"Qualifiers->SellerPositiveFeedbackRating",
					"NumberOfOfferListingsConsidered"=>"NumberOfOfferListingsConsidered",
					"SellerFeedbackCount"			=>"SellerFeedbackCount",
					"LandedPrice"					=>"Price->LandedPrice->Amount",
					"ListingPrice"					=>"Price->ListingPrice->Amount",
					"Shipping"						=>"Price->Shipping->Amount",
					"MultipleOffersAtLowestPrice"	=>"MultipleOffersAtLowestPrice"

);

foreach($xml->GetLowestOfferListingsForASINResult->Product->LowestOfferListings->LowestOfferListing as $key)
{
foreach($offer_url as $name=>$value)
{
echo  $name."->".$key->$value."--------";

}
echo "<br>";
}
  } 
    ?>

$key->$value没有结果，请问应该怎么写？？
------解决思路----------------------
echo eval("return $key->$value;");