Have a look here:
How to: Enumerate Directories and Files[
^]
Now, use
XDocument class[
^] to write data to xml file.
string dirPath = @"E:\DOWNLOAD\";
var dirs = Directory.EnumerateDirectories(dirPath)
.Where(d=>d.Contains("codeproject"));
var files = dirs.SelectMany(d=>Directory.EnumerateFiles(d, "*.pdf", SearchOption.AllDirectories));
XDocument xdoc = new XDocument();
XElement xRoot = new XElement("Files");
foreach (var f in files)
{
xRoot.Add(new XElement("File", f));
}
xdoc.Add(xRoot);
xdoc.Save("FullFileNameAndPath.xml");
Note: it's just simple sample, for large amount of data it might take a long time.