PHP-如何读取此XML文件

我有以下xml：

<CallOverview>
    <Calls Count="2">
        <Call CallType="LandLine" Customer="this account" StartTime="2013-09-17 20:21:19 (UTC)" Destination="NL" Duration="00:00:05" Charge="0.045" CallId="158263673"/>
        <Call CallType="Mobile" Customer="this account" StartTime="2013-09-17 20:18:34 (UTC)" Destination="US" Duration="00:00:26" Charge="0.101" CallId="158263381"/>
    </Calls>
<MoreData>No more data available</MoreData>
</CallOverview>

我根据需要接收XML，但无法以正确的方式提取数据：

$xml=simplexml_load_string ( get_xml($url_post) ) ;

echo $xml->getName() . "<br>";

foreach($xml->children() as $child)
{
    echo $child->getName() . ": " . $child . "<br>";

    foreach($child->children() as $subchild)
    {
        echo $subchild->getName() . ": " . $subchild . "<br>";
        $role = array($subchild->attributes());

        foreach($subchild as $key => $value) {
            echo "$role $key $value";            
        }
    }
}

我试过：

foreach($xml->Call[0]->attributes() as $a => $b) {
    echo $a,'="',$b,"\"\n";
}

但我得到了以下错误：

Fatal error: Call to a member function attributes() on a non-object

另外，如果没有呼叫，则不存在Call元素。

---

不熟悉xml，所以不确定是否可以在child下使用child

最后我使用了DOM解析器：

$dom_document = new DOMDocument();

$dom_document->loadXML(get_xml($url));

$searchNode = $dom_document->getElementsByTagName( "Call" );

if (!is_null($searchNode)) {
foreach( $searchNode as $searchNode )
{
    $Destination = $searchNode->getAttribute('Destination');
echo "$Destination";
}
}

---

会发生什么？什么意思

无法以正确的方式提取数据

？此代码输出什么？您希望它输出什么？我编辑了它，但不知怎么的，我没有从Callhm中获取属性。您在嵌套的foreach（更新的链接）中使用了两次$child

Fatal error: Call to a member function attributes() on a non-object

$dom_document = new DOMDocument();

$dom_document->loadXML(get_xml($url));

$searchNode = $dom_document->getElementsByTagName( "Call" );

if (!is_null($searchNode)) {
foreach( $searchNode as $searchNode )
{
    $Destination = $searchNode->getAttribute('Destination');
echo "$Destination";
}
}