PHP在嵌套对象的数组中的数组中的对象中选择XML属性

I'm having trouble grabbing and iterating through some XML data that is a bit buried. I can get the object to print_r but not just single attribute value.

Here is the simplified XML. Nests are accurate.

SimpleXMLElement Object ( 
    [@attributes] => Array ( 
    [amenity] => Array ( 
        [0] => SimpleXMLElement Object ( 
            [@attributes] => Array ( 
                [distance] => Within Facility 
                [name] => Biking 
            ) 
        ) 
        [1] => SimpleXMLElement Object ( 
            [@attributes] => Array ( 
                [distance] => Within Facility 
                [name] => Bird Watching 
            )
        )
...
)
)
)

I would like to grab/echo the name of each amenity.

$amenitiesSet = $xml->amenity;

foreach ($amenitiesSet as $am) {
    print_r($am[0]);    
}

Grabs each object. Every attempt to go deeper is failing. I know it is something simple that I am missing. I am not sure when to use [i], ['string'], -> etc. I am new to working with XML datasets.

Something like $am[0]->name?

OK so I finally figured out a solution. The trick with this was to loop over the objects in the object array then change the object attribute to a string. Then I could build the list. Here is the final loop code.

foreach($xml->amenity as $AMN){
            $amNameItem = (string)$AMN['name'];
            $amList .= $amNameItem.', ';
        }

No idea if this is the best solution, but at least I can get my list of object attributes from an array of objects in an array of xml objects.