File Encryption in mvc5 - encryption

Question

var graphids = from o in db.OfflineCarts
join i in db.Graphs on o.ItemId equals i.ItemUserID
select i;
GridView gv = new GridView();
gv.DataSource = graphids.ToList();
gv.DataBind();
Response.ClearContent();
Response.Buffer = true;
Response.AddHeader("content-disposition", "attachment; filename=GraphTable.xls");
Response.ContentType = "application/ms-excel";
Response.Charset = "";
StringWriter sw = new StringWriter();
HtmlTextWriter htw = new HtmlTextWriter(sw);
gv.RenderControl(htw);
Response.Output.Write(sw.ToString());
Response.Flush();
Response.End();
Encryption();
public void Encryption()
{
string password = #"myKey123"; // Your Key Here
UnicodeEncoding UE = new UnicodeEncoding();
byte[] key = UE.GetBytes(password);
string cryptFile = "/Users/Neeraj/Downloads/UserFilesEncrypt.xls";
FileStream fsCrypt = new FileStream(cryptFile, FileMode.CreateNew);
RijndaelManaged RMCrypto = new RijndaelManaged();
CryptoStream rs = new CryptoStream(fsCrypt,
RMCrypto.CreateEncryptor(key, key),
CryptoStreamMode.Read);
CryptoStream cs = new CryptoStream(fsCrypt,
RMCrypto.CreateEncryptor(key, key),
CryptoStreamMode.Write);
string inputFile = "/Users/Neeraj/Downloads/GraphTable.xls";
FileStream fsIn = new FileStream(inputFile, FileMode.Open);
int data;
while ((data = fsIn.ReadByte()) != -1)
cs.WriteByte((byte)data);
fsIn.Close();
cs.Close();
fsCrypt.Close();
}
I am encrypting the file just instantaneously after it is downloaded by grid view in mvc5 but i am getting 0 byte encrypted file and when i am re downloading the file than i am getting proper encrypted file Can Anybody tell me what is wrong with the code or i have to delay encryption function after download for sometime

Answer 1

use System.Security
FileStream fsInput = new FileStream(sInputFilename,
FileMode.Open,
FileAccess.Read);
FileStream fsEncrypted = new FileStream(sOutputFilename,
FileMode.Create,
FileAccess.Write);