选择节点与几个命名空间值的XML文档返回任何内容 [英] Selecting node with several namespaces values in XML document returns nothing

问题描述

有类似的XML文件：

<?xml version="1.0" encoding="UTF-8"?>
<Data Version="3" xsi:schemaLocation="uuid:ebfd9-45-48-a9eb-42d Data.xsd" xmlns="uuid:ebfd9-45-48-a9eb-42d" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
  <Info>
    <Muc>Demo</Muc>
  </Info>
</Data>

我做的。

I am doing

Dim m_xmld As XmlDocument
m_xmld = New XmlDocument()
m_xmld.Load("myXML.xml")
Dim test As XmlNode
test = doc.SelectSingleNode("Data/Info", GetNameSpaceManager(m_xmld))

有：

 Public Shared Function GetNameSpaceManager(ByRef xDoc As XmlDocument) As XmlNamespaceManager
        Dim nsm As New XmlNamespaceManager(xDoc.NameTable)
        Dim RootNode As XPathNavigator = xDoc.CreateNavigator()
        RootNode.MoveToFollowing(XPathNodeType.Element)
        Dim NameSpaces As IDictionary(Of String, String) = RootNode.GetNamespacesInScope(XmlNamespaceScope.All)
        For Each kvp As KeyValuePair(Of String, String) In NameSpaces
            nsm.AddNamespace(kvp.Key, kvp.Value)
        Next
        Return nsm
    End Function

不过，我不断获取无读取XML时。有没有办法忽略的命名空间？问题是，一些命名空间的文件可能有所不同，这就是为什么我添加 GetNameSpaceManager 函数...

However I keep on getting "Nothing" when reading the xml. Is there a way to ignore the namespaces?. The issue is that some namespaces may vary between files, thats why I added GetNameSpaceManager function...

推荐答案

在XPath中，没有前缀的元素名称空空间始终被认为。在XML中，虽然，有的默认命名空间的哪些元素隐含在默认情况下继承，这一个在特定的XML：

In XPath, element name without prefix is always considered in empty namespace. In XML though, there is default namespace which elements implicitly inherits by default, this one in your particular XML :

xmlns="uuid:ebfd9-45-48-a9eb-42d"

我想建议使用默认的前缀，比如 D ，在你的XPath。然后映射的前缀根元素的命名空间：

I'd suggest to use a default prefix, say d, in your XPath. And then map the prefix to the root element's namespace :

......
Dim nsManager As New XmlNamespaceManager(New NameTable())
nsManager.AddNamespace("d", m_xmld.DocumentElement.NamespaceURI)
test = doc.SelectSingleNode("d:Data/d:Info", nsManager)

上面将上这两种情况下工作（XML文档具有和不具有默认名称空间），但不是在情况下的与默认XML在命名空间后代元素级别本地声明。

The above will work on both cases (XML document with and without default namespace), but not in case an XML with default namespace declared locally at the descendant elements level.

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