SimpleXML从XML文件中获取特定数据

Question

我正在为JomSocial制作一个插件，该插件将基于XML文件显示登录用户的计费信息。我在创建插件方面取得了很好的进展，但我似乎无法正确使用语法来创建php语句，因此我可以在页面的各个位置填充数据。这是XML文件：

<Inquiry>
<Billing>
<Version>4.5.1</Version>
<startTime><![CDATA[4/15/2014 11:09 PM]]></startTime>
<endTime><![CDATA[4/15/2014 11:12 PM]]></endTime>
<Date>20140415</Date>
<MemberId ID="0ESING">
  <BillingInfo>
    <StatementEndDate>20140430</StatementEndDate>
    <BillingSubAccount>
    </BillingSubAccount>
    <BalanceForward>628.32</BalanceForward>
    <BalanceDue>372</BalanceDue>
    <Payments>-300</Payments>
</MemberId>
<MemberId ID="F00421">
</BillingInfo>
<BillingInfo>
<StatementEndDate>20140430</StatementEndDate>
 <BillingSubAccount>
 </BillingSubAccount>
 <BalanceForward>1158.36</BalanceForward>
 <BalanceDue>93.45</BalanceDue>
 <Payments>-1158.36</Payments>

以下是迄今为止的PHP：

$user =& CFactory::getRequestUser();
$cuser = CFactory::getUser();  
$owner = CFactory::getUser($row->user->id); 
$ptype = $cuser->getProfileType();
$billingid = $owner->getInfo('FIELD_BILLINGID');
$lastname = $owner->getInfo('FIELD_FAMILYNAME');
$uname = $cuser->username;
$memid = $cuser->id;
$name = $cuser->getDisplayName();
$isMine = COwnerHelper::isMine($cuser->id, $user->id);
$config = CFactory::getConfig();
$source = file_get_contents('data/201404.xml');
$xml = new SimpleXMLElement($source);
$balance = $xml->Billing->MemberId->BillingInfo->BalanceDue;
$BalanceForward = $xml->Billing->MemberId->BillingInfo->BalanceForward;
$Payments = $xml->Billing->MemberId->BillingInfo->Payments;
ob_start();
if( $isMine ) {
    if($ptype == '2') { 
    if(strcasecmp($uname, $billingid) == 0) {

然后，在页面中调用字段：

<?php echo "<div>Balance Due: $". $balance ." | Balance Forward: $" . $BalanceForward . " | Payment: $" . $Payments . "</div>"; ?>

这会拉入XML文件的第一条记录。我试了几个小时这样的东西：

$source = file_get_contents('data/201404.xml');
$xml = new SimpleXMLElement($source);
$balance = $xml->Billing->MemberId[.$uname.]->BillingInfo->BalanceDue;
$BalanceForward = $xml->Billing->MemberId[.$uname.]->BillingInfo->BalanceForward;
$Payments = $xml->Billing->MemberId[.$uname.]->BillingInfo->Payments;

但无济于事。我想从XML中"提取"子节点，其中MemberId="yadayada"等于$uname。我希望我是清楚的，这是我的第一个帖子栈溢出！

Answer 1

使用方括号表示法根据属性的名称访问属性，因此您要求member[0ESING]，这是不对的，因为属性名为ID。

您可以迭代成员以找到匹配项，如下所示：

foreach($xml->Billing->MemberId as $member){
    if($member['ID'] == $uname){
        $balance = $member->BillingInfo->BalanceDue;
        $BalanceForward = $member->BillingInfo->BalanceForward;
        $Payments = $member->BillingInfo->Payments;
    }
}

Answer 2

为什么不使用simplexml_load_file（）？它省去了手动加载文件并将其放入简单xml_element中的麻烦。此外，我认为问题的出现是因为XML文件本身无效，它需要1个根元素，但似乎包含零（或多个，取决于如何读取文件）。