在目录和子目录中搜索fast xml文件，查找c#中的数百万数据

public List<string> SearchXmlFiles(string directoryPath)
{
    List<string> xmlFiles = new List<string>();

    // 获取当前目录下的所有XML文件
    string[] files = Directory.GetFiles(directoryPath, "*.xml");
    xmlFiles.AddRange(files);

    // 遍历子目录
    string[] subDirectories = Directory.GetDirectories(directoryPath);
    foreach (string subDirectory in subDirectories)
    {
        xmlFiles.AddRange(SearchXmlFiles(subDirectory));
    }

    return xmlFiles;
}

public List<string> SearchDataInXmlFiles(List<string> xmlFiles, string searchData)
{
    List<string> results = new List<string>();

    foreach (string xmlFile in xmlFiles)
    {
        XmlDocument xmlDoc = new XmlDocument();
        xmlDoc.Load(xmlFile);

        // 使用XPath表达式查询数据
        XmlNodeList nodes = xmlDoc.SelectNodes("//data[contains(text(), '" + searchData + "')]");

        foreach (XmlNode node in nodes)
        {
            results.Add(node.InnerText);
        }
    }

    return results;
}

string directoryPath = "目标目录路径";
string searchData = "要搜索的数据";

List<string> xmlFiles = SearchXmlFiles(directoryPath);
List<string> searchResults = SearchDataInXmlFiles(xmlFiles, searchData);

foreach (string result in searchResults)
{
    Console.WriteLine(result);
}