send email with password protected pdf

Question

Currently in my program the data in crystal report is exported to pdf and send as email to clients.

But I need to send the pdf as password protected. This is my current code to send email with pdf attachment.

 

 

DataTable dt = new DataTable();

String str = "select * from table1 where (Num=@search) and (branch=@search1);";

SqlCommand xp = new SqlCommand(str, con);

xp.Parameters.Add("@search", SqlDbType.VarChar).Value = TextBox1.Text;

xp.Parameters.Add("@search1", SqlDbType.VarChar).Value = DropDownList1.SelectedValue;

con.Open();

SqlDataAdapter da = new SqlDataAdapter();

da.SelectCommand = xp;

da.Fill(dt);

con.Close();

if (dt.Rows.Count > 0)

{

ReportDocument crystalReport = new ReportDocument();

crystalReport.SetDatabaseLogon("xxxxx", "xxxxxx");

crystalReport.SetDataSource(dt1);

CrystalReportViewer1.ReportSource = crystalReport;

CrystalReportViewer1.DataBind();

using (MailMessage mm = new MailMessage("xxxxxxx", "xxxxxxxx"))

{

mm.Subject = "Test";

mm.Attachments.Add(new Attachment(crystalReport.ExportToStream(ExportFormatType.PortableDocFormat), "Report.pdf"));

mm.IsBodyHtml = true;

SmtpClient smtp = new SmtpClient();

smtp.Host = "smtp.google.com";

NetworkCredential credential = new NetworkCredential();

credential.UserName = "xxxxxxxx";

credential.Password = "xxxxxxxx";

smtp.UseDefaultCredentials = true;

smtp.Credentials = credential;

smtp.Port = 587;

smtp.EnableSsl = false;

smtp.Send(mm);

}

ScriptManager.RegisterClientScriptBlock(this, this.GetType(),

"alertMessage",

"alert('message send successfully');", true);

}