如何最好地在.NET中使用XPath和非常大的XML文件？

using System.Xml;
using System.Xml.XPath;

XPathDocument xpathDoc = new XPathDocument("large_xml_file.xml");
XPathNavigator xpathNav = xpathDoc.CreateNavigator();

XPathExpression expr = xpathNav.Compile("/root/element");
XPathNodeIterator iterator = xpathNav.Select(expr);

while (iterator.MoveNext())
{
    // 处理每个匹配的节点
}

using System.Xml;
using System.Xml.Linq;

XDocument xDoc = null;
using (XmlReader xmlReader = XmlReader.Create("large_xml_file.xml"))
{
    xDoc = XDocument.Load(xmlReader);
}

var result = xDoc.XPathSelectElements("/root/element");

using System.Xml;

using (XmlReader reader = XmlReader.Create("large_xml_file.xml"))
using (XmlWriter writer = XmlWriter.Create("output.xml"))
{
    reader.MoveToContent();
    while (reader.Read())
    {
        if (reader.NodeType == XmlNodeType.Element && reader.Name == "element")
        {
            // 处理每个匹配的节点
            writer.WriteNode(reader, false);
        }
    }
}

using System.Xml.Linq;

XStreamingElement streamingElement = new XStreamingElement("root",
    from element in XElement.Load("large_xml_file.xml").Elements("element")
    select new XElement("element", element.Attribute("id"), element.Value)
);
streamingElement.Save("output.xml");