Security C# Tutorial

using System;
using System.IO;
using System.Security;
using System.Security.Cryptography;
using System.Collections.Generic;
using System.Text;
    class Program
    {
        static void Main(string[] args)
        {
            StreamReader sr = File.OpenText("myKey.xml");
            string myKey = sr.ReadToEnd();
            sr.Close();
            RSACryptoServiceProvider rsa = new RSACryptoServiceProvider();
            rsa.FromXmlString(myKey);
            FileStream fs = new FileStream("Message.dat", FileMode.Open);
            byte[] encrypted = new byte[fs.Length];
            fs.Read(encrypted, 0, (int)fs.Length);
            byte[] decrypted = rsa.Decrypt(encrypted, false);
            fs.Close();
            Console.WriteLine(System.Text.ASCIIEncoding.ASCII.GetString(decrypted));
            
        }
    }