How can I encrypt a querystring in asp.net?

Question

I need to encrypt and decrypt a querystring in ASP.NET.

The querystring might look something like this:

http://www.mysite.com/report.aspx?id=

Answer 1

Encryption in C# using AES encryption-

protected void Submit(object sender, EventArgs e)
{
    string name = HttpUtility.UrlEncode(Encrypt(txtName.Text.Trim()));
    string technology = HttpUtility.UrlEncode(Encrypt(ddlTechnology.SelectedItem.Value));
    Response.Redirect(string.Format("~/CS2.aspx?name={0}&technology={1}", name, technology));
}

AES Algorithm Encryption and Decryption functions

private string Encrypt(string clearText)
{
    string EncryptionKey = "hyddhrii%2moi43Hd5%%";
    byte[] clearBytes = Encoding.Unicode.GetBytes(clearText);
    using (Aes encryptor = Aes.Create())
    {
        Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
        encryptor.Key = pdb.GetBytes(32);
        encryptor.IV = pdb.GetBytes(16);
        using (MemoryStream ms = new MemoryStream())
        {
            using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateEncryptor(), CryptoStreamMode.Write))
            {
                cs.Write(clearBytes, 0, clearBytes.Length);
                cs.Close();
            }
            clearText = Convert.ToBase64String(ms.ToArray());
        }
    }
    return clearText;
}


private string Decrypt(string cipherText)
{
    string EncryptionKey = "hyddhrii%2moi43Hd5%%";
    cipherText = cipherText.Replace(" ", "+");
    byte[] cipherBytes = Convert.FromBase64String(cipherText);
    using (Aes encryptor = Aes.Create())
    {
        Rfc2898DeriveBytes pdb = new Rfc2898DeriveBytes(EncryptionKey, new byte[] { 0x49, 0x76, 0x61, 0x6e, 0x20, 0x4d, 0x65, 0x64, 0x76, 0x65, 0x64, 0x65, 0x76 });
        encryptor.Key = pdb.GetBytes(32);
        encryptor.IV = pdb.GetBytes(16);
        using (MemoryStream ms = new MemoryStream())
        {
            using (CryptoStream cs = new CryptoStream(ms, encryptor.CreateDecryptor(), CryptoStreamMode.Write))
            {
                cs.Write(cipherBytes, 0, cipherBytes.Length);
                cs.Close();
            }
            cipherText = Encoding.Unicode.GetString(ms.ToArray());
        }
    }
    return cipherText;
}

To Decrypt

lblName.Text = Decrypt(HttpUtility.UrlDecode(Request.QueryString["name"]));
lblTechnology.Text = Decrypt(HttpUtility.UrlDecode(Request.QueryString["technology"]));