选择特定的子节点/元素

我总是听到有人说："嘿，迈克，别担心，如果它让你感到沮丧，那就让它过去，做你的日常冥想"。

开玩笑！也许您应该尝试使用nampespace管理器。我自己项目中的小代码摘录。

        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.Load(ConfigFile);
        XmlNamespaceManager xmlnsm = new XmlNamespaceManager(xmlDoc.NameTable);
        xmlnsm.AddNamespace("h", "urn:nhibernate-configuration-2.2");
        XmlElement root = xmlDoc.DocumentElement;
        //Do you XML magic here with namespace included
        XmlNodeList Properties = root.SelectNodes("h:session-factory/h:property[@name='connection.connection_string']", xmlnsm);

编辑：为了完成，这是代码正在处理的XML文件。

<?xml version="1.0" encoding="utf-8"?>
<!-- 
This template was written to work with NHibernate.Test.
Copy the template to your NHibernate.Test project folder and rename it in hibernate.cfg.xml and change it 
for your own use before compile tests in VisualStudio.
-->
<!-- This is the ByteFX.Data.dll provider for MySql -->
<hibernate-configuration  xmlns="urn:nhibernate-configuration-2.2" >
    <session-factory name="NHibernate.Test">
        <property name="connection.driver_class">NHibernate.Driver.MySqlDataDriver</property>
        <property name="connection.connection_string">
      Data Source=127.0.0.1;Port=3307;MyUser Id=root;Password=MyPassword;Database=MyDatabase;
    </property>
        <property name="dialect">NHibernate.Dialect.MySQLDialect</property>
    </session-factory>
</hibernate-configuration>

可以使用这样的类来执行从一种 XML 类型到另一种 XML 类型的转换。 我更喜欢 Linq-to-XML，所以我将展示这一点：

public static class XmlLinqConversionExtensions
{
    /// <summary>
    /// Converts an XDocument to an XmlDocument.
    /// </summary>
    /// <param name="xdoc">The XDocument to convert.</param>
    /// <returns>The equivalent XmlDocument.</returns>
    public static XmlDocument ToXmlDocument(this XDocument xdoc)
    {
        var xmldoc = new XmlDocument();
        xmldoc.Load(xdoc.CreateReader());
        return xmldoc;
    }
    /// <summary>
    /// Convert an XElement to an XmlDocument.
    /// </summary>
    /// <param name="xelement"></param>
    /// <returns></returns>
    public static XmlDocument ToXmlDocument(this XElement xelement)
    {
        var xmldoc = new XmlDocument();
        xmldoc.Load(xelement.CreateReader());
        return xmldoc;
    }
    /// <summary>
    /// Converts an XmlDocument to an XDocument.
    /// </summary>
    /// <param name="xmldoc">The XmlDocument to convert.</param>
    /// <returns>The equivalent XDocument.</returns>
    public static XDocument ToXDocument(this XmlDocument xmldoc)
    {
        return XDocument.Load(xmldoc.CreateNavigator().ReadSubtree());
    }
    /// <summary>
    /// Converts an XmlDocument to an XElement.
    /// </summary>
    /// <param name="xmldoc"></param>
    /// <returns></returns>
    public static XElement ToXElement(this XmlDocument xmldoc)
    {
        return ToXDocument(xmldoc).Root;
    }
    /// <summary>
    /// Converts an XElement to an XmlElement.
    /// </summary>
    /// <param name="xelement">The XElement to convert.</param>
    /// <returns>The equivalent XmlElement.</returns>
    public static XmlElement ToXmlElement(this XElement xelement)
    {
        return new XmlDocument().ReadNode(xelement.CreateReader()) as XmlElement;
    }
    /// <summary>
    /// Converts an XmlElement to an XElement.
    /// </summary>
    /// <param name="xmlelement">The XmlElement to convert.</param>
    /// <returns>The equivalent XElement.</returns>
    public static XElement ToXElement(this XmlElement xmlelement)
    {
        return XElement.Load(xmlelement.CreateNavigator().ReadSubtree());
    }
}

因此，您首先将节点转换为 XElement。

XElement xnode = node.ToXElement();

然后选择所有文档 ID：

XNamespace ns = "http://usop.ctadvantage.com/";
var docIds = xnode.Descendants(ns + "DocId");

和/或通过其 Id 值获取特定节点：

XElement specificdocId = docIds.Where(x => x.Value == "965F53E3C702").FirstOrDefault();