parsing - 访问特定节点 (custom_field) simplexml

Question

此 XML 文件可在此处访问 @ http://afdclinics.com/persistentpresence/category/brentwood/lobby-1/feed/ - 有一个 custom_fields 节点，其中包含两个字段，称为 custom-bgcolor 和 custom-fontcolor。我已经尝试了很多方法来尝试，并且没有运气访问其中的数据。

我一直在使用 simplexml 访问其他节点，但无法让 custom_fields 正常工作。这是我到目前为止所拥有的。

$curl = curl_init();        
curl_setopt ($curl, CURLOPT_URL,'http://afdclinics.com/persistentpresence/category/brentwood/lobby-1/feed/');   
curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);   
$result = curl_exec ($curl);   

if ($result === false) {
die('Error fetching data: ' . curl_error($curl));   
}
curl_close ($curl);    

//we can at this point echo the XML if you want
//echo $result;

//parse xml string into SimpleXML objects
$xml = simplexml_load_string($result);

if ($xml === false) {
die('Error parsing XML');   
}

//now we can loop through the xml structure
foreach ($xml->channel->item as $item) {
//print $item->title;       rss feed article title
//print $item->description; rss feed article description
//print $item->link;        rss feed article link
//print $item->pubDate;     rss feed article publish date
print $item->children('content', true); //rss feed article content


// here is where is would like to print the custom values
    print $item->custom_fields->custom-bgcolor;  // this line doesn't seem to work

//gets img url's and appends them to offline manifest file
$imgUrl = array();  
$doc2 = new DOMDocument();
$doc2->loadHTML($item->children('content', true));
$imgUrl = simplexml_import_dom($doc2);
$images = $imgUrl->xpath('//img');

foreach ($images as $img) {                     
    $imgUrl = $img['src'] . "\r\n"; 
    print $imgUrl;      //rss feed image url's
    $i++;
}