Evet de aşağıdaki şekilde ana ağacı aldım. burada sorun şu her ana ağacın altında da ShipmentDetail var. bunları da almam lazım. sorunu burada yaşıyorum.
$Shipment = simplexml_load_file("http://www.f2r.gen.tr/sevkiyat.xml");
foreach ($Shipment as $Shipmentinfo):
$ShipmentNumber=$Shipmentinfo['ShipmentNumber'];
$InvoiceNumber=$Shipmentinfo['InvoiceNumber'];
$ShipmentDate=$Shipmentinfo['ShipmentDate'];
$TruckPlate=$Shipmentinfo['TruckPlate'];
$ContainerNumber=$Shipmentinfo['ContainerNumber'];
$DispatchDate=$Shipmentinfo['DispatchDate'];
echo "ShipmentNumber : ".$ShipmentNumber."<br>";
echo "InvoiceNumber : ".$InvoiceNumber."<br>";
echo "ShipmentDate : ".$ShipmentDate."<br>";
echo "TruckPlate : ".$TruckPlate."<br>";
echo "ContainerNumber : ".$ContainerNumber."<br>";
echo "DispatchDate : ".$DispatchDate."<hr>";
endforeach;
haa tamam.

şimdi daha net oldu problem.
Şöyle alabilirsiniz.
$Shipment = simplexml_load_file("http://www.f2r.gen.tr/sevkiyat.xml");
foreach ($Shipment as $Shipmentinfo):
$ShipmentNumber = $Shipmentinfo['ShipmentNumber'];
$InvoiceNumber = $Shipmentinfo['InvoiceNumber'];
$ShipmentDate = $Shipmentinfo['ShipmentDate'];
$TruckPlate = $Shipmentinfo['TruckPlate'];
$ContainerNumber = $Shipmentinfo['ContainerNumber'];
$DispatchDate = $Shipmentinfo['DispatchDate'];
echo "ShipmentNumber : " . $ShipmentNumber . "<br>";
echo "InvoiceNumber : " . $InvoiceNumber . "<br>";
echo "ShipmentDate : " . $ShipmentDate . "<br>";
echo "TruckPlate : " . $TruckPlate . "<br>";
echo "ContainerNumber : " . $ContainerNumber . "<br>";
echo "DispatchDate : " . $DispatchDate . "<hr>";
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['BdtCode'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['ProdcutCode'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['Quantity'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['OrderReference'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['BdtOrderNumber'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['CustomerItemReference'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['CustomerItemCode'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['CustomerOrderReference'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['ProductName_Tr'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['ProductName_En'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['Unit'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['Volume'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['Weight'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['ProductName'];
echo $Shipmentinfo->Detail->ShipmentDetail->attributes()['PackageCount'];
endforeach;