Password-Protected PDF File Using ASP.Net C#

private void wordProtectedPDF()
{
    StringWriter sw = new StringWriter();
    HtmlTextWriter hw = new HtmlTextWriter(sw);
    GridView1.RenderControl(hw);
    StringReader sr = new StringReader(sw.ToString());
    
    Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 0f);
    HTMLWorker htmlworker = new HTMLWorker(pdfDoc);
    
    using (MemoryStream ObjememoryStream = new MemoryStream())
    {
        PdfWriter.GetInstance(pdfDoc, ObjememoryStream);
        pdfDoc.Open();
        htmlworker.Parse(sr);
        pdfDoc.Close();
        byte[] Filebytes = ObjememoryStream.ToArray();
        ObjememoryStream.Close();
        
        using (MemoryStream inputData = new MemoryStream(Filebytes))
        {
            using (MemoryStream outputData = new MemoryStream())
            {
                string PDFFileword = "vithal@C#cornerDemo"; // you can also generate Dynamic word
                PdfReader reader = new PdfReader(inputData);
                PdfEncryptor.Encrypt(reader, outputData, true, PDFFileword, PDFFileword, PdfWriter.ALLOW_SCREENREADERS);
                Filebytes = outputData.ToArray();
                Response.ContentType = "application/pdf";
                Response.AddHeader("content-disposition", "attachment;filename=GridViewExport.pdf");
                Response.Cache.SetCacheability(HttpCacheability.NoCache);
                Response.BinaryWrite(Filebytes);
                Response.End();
                GridView1.AllowPaging = true;
                GridView1.DataBind();
            }
        }
    }
}

Now call the above method on the export button and click as.

protected void Button1_Click(object sender, EventArgs e)
{
    //calling method to generate word Protected PDF
    wordProtectedPDF();
}

Now the entire code of the Default. aspx.cs page will be as follows.

using System;
using System.Web.UI;
using System.Configuration;
using System.Data.SqlClient;
using System.IO;
using System.Web;
using iTextSharp.text;
using iTextSharp.text.pdf;
using iTextSharp.text.html.simpleparser;

public partial class _Default : System.Web.UI.Page
{
    private SqlConnection con;
    private SqlCommand com;
    private string constr, query;

    private void connection()
    {
        constr = ConfigurationManager.ConnectionStrings["getconn"].ToString();
        con = new SqlConnection(constr);
        con.Open();
    }
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!IsPostBack)
        {
            Bindgrid();
        }
    }
    public override void VerifyRenderingInServerForm(Control control)
    {
        //required to avoid the runtime error "Control 'GridView1' of type 'GridView' must be placed inside a form tag with runat=server."
    }

    private void Bindgrid()
    {
        connection();
        query = "select * from Employee"; // not recommended this, I have written just for example, write stored procedure for security
        com = new SqlCommand(query, con);
        SqlDataReader dr = com.ExecuteReader();
        GridView1.DataSource = dr;
        GridView1.DataBind();
        con.Close();
    }
    protected void Button1_Click(object sender, EventArgs e)
    {
        // calling method to generate word Protected PDF
        wordProtectedPDF();
    }
    private void wordProtectedPDF()
    {
        StringWriter sw = new StringWriter();
        HtmlTextWriter hw = new HtmlTextWriter(sw);
        GridView1.RenderControl(hw);
        StringReader sr = new StringReader(sw.ToString());

        Document pdfDoc = new Document(PageSize.A4, 10f, 10f, 10f, 0f);
        HTMLWorker htmlworker = new HTMLWorker(pdfDoc);

        using (MemoryStream ObjememoryStream = new MemoryStream())
        {
            PdfWriter.GetInstance(pdfDoc, ObjememoryStream);
            pdfDoc.Open();
            htmlworker.Parse(sr);
            pdfDoc.Close();
            byte[] Filebytes = ObjememoryStream.ToArray();
            ObjememoryStream.Close();

            using (MemoryStream inputData = new MemoryStream(Filebytes))
            {
                using (MemoryStream outputData = new MemoryStream())
                {
                    string PDFFileword = "vithal@C#cornerDemo"; // you can also generate Dynamic word
                    PdfReader reader = new PdfReader(inputData);
                    PdfEncryptor.Encrypt(reader, outputData, true, PDFFileword, PDFFileword, PdfWriter.ALLOW_SCREENREADERS);
                    Filebytes = outputData.ToArray();
                    Response.ContentType = "application/pdf";
                    Response.AddHeader("content-disposition", "attachment;filename=GridViewExport.pdf");
                    Response.Cache.SetCacheability(HttpCacheability.NoCache);
                    Response.BinaryWrite(Filebytes);
                    Response.End();
                    GridView1.AllowPaging = true;
                    GridView1.DataBind();
                }
            }
        }
    }
}

Now run the application and click on the Export Button. The following popup is shown.

Now click on the open with option. It will then prompt you to enter a word as.

Now enter an incorrect word and it will show the following message.

Now enter the correct word as vithal@C#cornerDemo, and then the file will be opened with the following records.

Note

• Download the Zip file from the attachment for the full source code of an application.
• Change the connection string from the web. config file as per your server location.
• You can also send this file through an email as an attachment on the Export button click by creating an email method.

Summary

I hope this article is useful for all readers, if you have any suggestion then please contact me including beginners also.