File Stream C#

using System;
    using System.IO;
    class Touch
    {
        static void Main(string[] args)
        {
            FileInfo fi = new FileInfo("c:\\a.txt");
            touchFile(fi);
        }
        static void touchFile(FileSystemInfo fsi)
        {
            Console.WriteLine("Touching: {0}", fsi.FullName);
            try
            {
                fsi.CreationTime = fsi.LastWriteTime = fsi.LastAccessTime = DateTime.Now;
            }
            catch (Exception e)
            {
                Console.WriteLine("Error: {0}", e.Message);
            }
        }
    }