C#

void exited_event(object sender, EventArgs e)
{
listview1.Items[0].SubItems[0].Text = "abc";
}

public static void EncryptToFile(string ConfigData, string FilePath)
      {
          FileStream fStream = File.Open(FilePath, FileMode.OpenOrCreate);
          Rijndael RijndaelObject = Rijndael.Create();
          ICryptoTransform encryptor = RijndaelObject.CreateEncryptor(key, IV);
          CryptoStream csEncrypt = new CryptoStream(fStream, encryptor, CryptoStreamMode.Write);
          StreamWriter sw = new StreamWriter(csEncrypt);
          sw.WriteLine(ConfigData);
          sw.Close();
          csEncrypt.Close();
          fStream.Close();
      }