xPath只能找到* [英] xPath finds nothing but *

问题描述

这开始让我很生气.我有以下XML代码:

This is starting to piss me off real bad. I have this XML code:

已使用正确的命名空间更新

<?xml version="1.0" encoding="utf-8"?>

<Infringement xsi:schemaLocation="http://www.movielabs.com/ACNS http://www.movielabs.com/ACNS/ACNS2v1.xsd" xmlns="http://www.movielabs.com/ACNS" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Case>
    <ID>...</ID>
    <Status>Open</Status>
  </Case>
  <Complainant>
    <Entity>...</Entity>
    <Contact>...</Contact>
    <Address>...</Address>
    <Phone>...</Phone>
    <Email>...</Email>
  </Complainant>
  <Service_Provider>
    <Entity>...</Entity>
    <Address></Address>
    <Email>...</Email>
  </Service_Provider>
  <Source>
    <TimeStamp>...</TimeStamp>
    <IP_Address>...</IP_Address>
    <Port>...</Port>
    <DNS_Name></DNS_Name>
    <Type>...</Type>
    <UserName></UserName>
    <Number_Files>1</Number_Files>
    <Deja_Vu>No</Deja_Vu>
  </Source>
  <Content>
    <Item>
      <TimeStamp>...</TimeStamp>
      <Title>...</Title>
      <FileName>...</FileName>
      <FileSize>...</FileSize>
      <URL></URL>
    </Item>
  </Content>
</Infringement>

此PHP代码:

<?php 
    $data = urldecode($_POST["xml"]);
    $newXML = simplexml_load_string($data);

    var_dump($newXML->xpath("//ID"));
?>

我只转储了$ newXML并获得了大量数据，但是我运行过的唯一返回空数组的xPath是"*"

I've dumped only $newXML and gotten tons of data, but the only xPath I've run that returned anything but an empty array was "*"

"//ID"不是应该在文档中找到所有ID节点吗?为什么不起作用?

Isn't "//ID" supposed to find all ID nodes in the document? Why isn't it working?

谢谢

推荐答案

我只转储了$ newXML并得到了 大量的数据，但是我仅有的xPath 运行返回任何东西，但 空数组为"*"

I've dumped only $newXML and gotten tons of data, but the only xPath I've run that returned anything but an empty array was "*"

那么var_dump($newXML->xpath("*"));返回了什么? <Infringement>?

如果问题是名称空间，请尝试以下操作:

var_dump($newXML->xpath("//*[local-name() = 'ID']"));

这将匹配文档中名称为'ID'的任何元素，而与命名空间无关.

This will match any element in the document whose name is 'ID', regardless of namespace.

如果我全部替换掉​​，我的东西就会起作用 "xmlns"和"ns"

My stuff works if i replace all "xmlns" with "ns"

等等，什么?您确定您向我们展示了文档中所有与xmlns相关的属性吗?

Wait, what? Are you sure you showed us all the xmlns-related attributes in the document?

更新: 对问题进行了编辑，以显示XML确实具有默认的名称空间声明.这就解释了最初的问题:由于默认的命名空间声明，您的XPath表达式选择了没有命名空间的ID元素，但是文档中的元素却位于movielabs ACNS命名空间中.

Update: The question was edited to show that the XML really does have a default namespace declaration. That explains the original problem: your XPath expression selects ID elements that are in no namespace, but the elements in your document are in the movielabs ACNS namespace, thanks to the default namespace declaration.

元素上的声明xmlns="http://www.movielabs.com/ACNS"表示此元素和所有没有名称空间前缀(例如ID)的子代均位于名称空间URI'

The declaration xmlns="http://www.movielabs.com/ACNS" on an element means "this element and all descendants that don't have a namespace prefix (like ID) are in the namespace represented by the namespace URI 'http://www.movielabs.com/ACNS'." (Unless an intervening descendant has a different default namespace declaration, which would shadow this one.)

因此，请使用我上面的local-name()答案忽略名称空间，或使用jasso的技术来指定movielabs ACNS并按预期使用它.

So use my local-name() answer above to ignore namespaces, or use jasso's technique to specify the movielabs ACNS and use it as intended.

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