如何使用子节点获取PHP简单的XML值？

Question

我有一个XML，如图所示。我需要为每个循环遍历标记并提取属性attr1。但我经常得到"Illegal string offset"。

我的数据：

<Parent>
  <Child>
    <ID attr1="123" attr2="567">abc</ID>
    <ID attr1="123" attr2="567">abc</ID>
  </Child>
</Parent>

我的代码：

foreach ($parentNode->Child->ID as $IDChild => $value)
{
    echo $value; // does this output "abc"?
    echo $IDChild['attr1']; // need to display "123", but throwing error.
    $IDChild['attr1'] = "999"; // also need to update the value in the xml
}

Answer 1

<?php
$oXml = new SimpleXMLElement('<Parent>
  <Child>
    <ID attr1="123" attr2="567">abc</ID>
    <ID attr1="123" attr2="567">abc</ID>
  </Child>
</Parent>');

foreach($oXml->Child->ID as $oXml)
    var_dump((string)$oXml['attr1']);