using System.IO;
string[] files = Directory.GetFiles(dirName);
foreach (string file in files)
{
FileInfo fi = new FileInfo(file);
if (fi.LastAccessTime < DateTime.Now.AddDays(-10))
fi.Delete();
}
using System.IO;
string[] files = Directory.GetFiles(dirName);
foreach (string file in files)
{
FileInfo fi = new FileInfo(file);
if (fi.LastAccessTime < DateTime.Now.AddMonths(-3))
fi.Delete();
}