PHP | SimpleXMLIterator getChildren()函数

SimpleXMLIterator getChildren()函数是一个用于获取SimpleXMLIterator对象下一级子节点的方法，该方法返回一个SimpleXMLIterator对象，用于遍历获取到的子节点。该方法非常适合用于遍历XML文件中的子节点。

语法

SimpleXMLIterator SimpleXMLIterator::getChildren([string $ns = "" [, bool $is_prefix = false]]);

参数说明：

• $ns：可选参数，用于指定子节点的命名空间。
• $is_prefix：可选参数，设置是否将$ns参数解释为一个命名空间前缀。

返回值

• 如果存在子节点，该方法返回一个SimpleXMLIterator对象，可以用于获取这些子节点。
• 如果未指定子节点的命名空间，子节点是SimpleXMLElement对象，如果指定了命名空间，则子节点是SimpleXMLIterator对象。

示例

遍历未指定命名空间的子节点

$xml = '<?xml version="1.0" encoding="UTF-8"?>
<catalog>
   <book id="bk101">
      <author>Gambardella, Matthew</author>
      <title>XML Developer\'s Guide</title>
      <genre>Computer</genre>
      <price>44.95</price>
      <publish_date>2000-10-01</publish_date>
      <description>An in-depth look at creating applications 
      with XML.</description>
   </book>
   <book id="bk102">
      <author>Ralls, Kim</author>
      <title>Midnight Rain</title>
      <genre>Fantasy</genre>
      <price>5.95</price>
      <publish_date>2000-12-16</publish_date>
      <description>A former architect battles corporate zombies, 
      an evil sorceress, and her own childhood to become queen 
      of the world.</description>
   </book>
</catalog>';
$iterator = new SimpleXMLIterator($xml);
foreach ($iterator->getChildren() as $book) {
   echo $book->author . '<br>';
   echo $book->title . '<br>';
}

输出结果：

Gambardella, Matthew
XML Developer's Guide
Ralls, Kim
Midnight Rain

遍历指定命名空间的子节点

$xml = '<?xml version="1.0" encoding="UTF-8"?>
<catalog xmlns:book="http://example.com/book">
   <book:book id="bk101">
      <book:author>Gambardella, Matthew</book:author>
      <book:title>XML Developer\'s Guide</book:title>
      <book:genre>Computer</book:genre>
      <book:price>44.95</book:price>
      <book:publish_date>2000-10-01</book:publish_date>
      <book:description>An in-depth look at creating applications 
      with XML.</book:description>
   </book:book>
   <book:book id="bk102">
      <book:author>Ralls, Kim</book:author>
      <book:title>Midnight Rain</book:title>
      <book:genre>Fantasy</book:genre>
      <book:price>5.95</book:price>
      <book:publish_date>2000-12-16</book:publish_date>
      <book:description>A former architect battles corporate zombies, 
      an evil sorceress, and her own childhood to become queen 
      of the world.</book:description>
   </book:book>
</catalog>';
$iterator = new SimpleXMLIterator($xml);
foreach ($iterator->getChildren('http://example.com/book', true) as $book) {
   echo $book->author . '<br>';
   echo $book->title . '<br>';
}

输出结果：

Gambardella, Matthew
XML Developer's Guide
Ralls, Kim
Midnight Rain

总结

SimpleXMLIterator getChildren()函数可用于获取SimpleXMLIterator对象下一级子节点，适用于解析XML文件并遍历其中的子节点。该方法返回一个SimpleXMLIterator对象，可以用于获取这些子节点。需要注意的是，如果指定子节点的命名空间，子节点返回的对象为SimpleXMLIterator对象。