php - 如何使用 PHP DOMDocument 删除属性？

Question

有了这段 XML:

<my_xml>
  <entities>
    <image url="lalala.com/img.jpg" id="img1" />
    <image url="trololo.com/img.jpg" id="img2" />
  </entities>
</my_xml> 

我必须去掉图像标签中的所有属性。所以，我这样做了:

<?php

$article = <<<XML
<my_xml>
  <entities>
    <image url="lalala.com/img.jpg" id="img1" />
    <image url="trololo.com/img.jpg" id="img2" />
  </entities>
</my_xml>  
XML;

$doc = new DOMDocument();
$doc->loadXML($article);
$dom_article = $doc->documentElement;
$entities = $dom_article->getElementsByTagName("entities");

foreach($entities->item(0)->childNodes as $child){ // get the image tags
  foreach($child->attributes as $att){ // get the attributes
    $child->removeAttributeNode($att); //remove the attribute
  }
}

?>

不知何故，当我尝试从 foreach block 中删除一个 from 属性时，看起来内部指针丢失了并且它没有同时删除这两个属性。

还有其他方法吗？

提前致谢。

Answer 1

将内部 foreach 循环更改为:

while ($child->hasAttributes())
  $child->removeAttributeNode($child->attributes->item(0));

或者回到前面删除:

if ($child->hasAttributes()) { 
  for ($i = $child->attributes->length - 1; $i >= 0; --$i)
    $child->removeAttributeNode($child->attributes->item($i));
}

或者复制属性列表:

if ($child->hasAttributes()) {
  foreach (iterator_to_array($child->attributes) as $attr)
    $child->removeAttributeNode($attr);
}

这些都行。