Originally Posted by night.rider

sir really ... this adding password to pdf works and i wrote in C#.net
it really works... awesome yaar...

sir can u tell me if before encryption the pdf is encrypted then wat to do becoz the pdfencrypter gives error...

sir please , if more u can tell abt all this and more

        private void btnopen_Click(object sender, EventArgs e)
        {
            OpenFileDialog FldBrow = new OpenFileDialog();
            FldBrow.Title = "Select PDF To Add Password";
            FldBrow.InitialDirectory="c:\\";
            FldBrow.Filter = "PDF Files (*.pdf)|*.pdf";
            FldBrow.FilterIndex = 2;
            FldBrow.RestoreDirectory=true;
            if(FldBrow.ShowDialog() == System.Windows.Forms.DialogResult.OK)
                textBox1.Text=FldBrow.FileName;
        }

        private void Save_Click(object sender, EventArgs e)
        {
            SaveFileDialog sfd1=new SaveFileDialog();
            sfd1.Title = "Save Output File";
            sfd1.InitialDirectory = "My Documents\\";
            sfd1.Filter = "PDF files (*.pdf)|*.pdf";
            sfd1.FilterIndex = 2;
            sfd1.RestoreDirectory = true;
            if(sfd1.ShowDialog()==System.Windows.Forms.DialogResult.OK)
                textBox2.Text=sfd1.FileName;
        }

        private void addpwd_Click(object sender, EventArgs e)
        {
            string input = "";
            string output = "";
            string password = "";
            input = textBox1.Text;
            output = textBox2.Text;
            password = txtpass.Text;

            Add_pwd_to_pdf(input, output, password);
        }

        private void Add_pwd_to_pdf(string input, string output, string password)
        {
            //string ownpwd = "123";
            PdfReader preader = new PdfReader(input);
            PdfEncryptor.Encrypt(preader, new FileStream(output, FileMode.Append), PdfWriter.STRENGTH128BITS, password,"",PdfWriter.ALLOW_SCREENREADERS);
        }