使用C#从两个文件复制不同的节点，并将其粘贴到第三个文件上

StreamReader reader1 = new StreamReader("file1.txt");
StreamReader reader2 = new StreamReader("file2.txt");

string file1Content = reader1.ReadToEnd();
string file2Content = reader2.ReadToEnd();

reader1.Close();
reader2.Close();

XmlDocument doc1 = new XmlDocument();
doc1.LoadXml(file1Content);

XmlDocument doc2 = new XmlDocument();
doc2.LoadXml(file2Content);

XmlNodeList nodes1 = doc1.SelectNodes("//node");
XmlNodeList nodes2 = doc2.SelectNodes("//node");

XmlDocument doc3 = new XmlDocument();
XmlNode rootNode = doc3.CreateElement("root");
doc3.AppendChild(rootNode);

foreach (XmlNode node1 in nodes1)
{
    bool isDifferent = true;

    foreach (XmlNode node2 in nodes2)
    {
        if (node1.OuterXml == node2.OuterXml)
        {
            isDifferent = false;
            break;
        }
    }

    if (isDifferent)
    {
        XmlNode importedNode = doc3.ImportNode(node1, true);
        rootNode.AppendChild(importedNode);
    }
}

doc3.Save("file3.txt");