    private void convertToPdfButton_Click(object sender, EventArgs e)
    {
        // Create a HTML to PDF converter object with default settings
        HtmlToPdfConverter htmlToPdfConverter = new HtmlToPdfConverter();

        // Set license key received after purchase to use the converter in licensed mode
        // Leave it not set to use the converter in demo mode
        htmlToPdfConverter.LicenseKey = "4W9+bn19bn5ue2B+bn1/YH98YHd3d3c=";

        // Set an adddional delay in seconds to wait for JavaScript or AJAX calls after page load completed
        // Set this property to 0 if you don't need to wait for such asynchcronous operations to finish
        htmlToPdfConverter.ConversionDelay = 2;

        // Set the encryption algorithm and the encryption key size if they are not the default ones
        if (!bit128RadioButton.Checked || !rc4RadioButton.Checked)
        {
            // set the encryption algorithm
            htmlToPdfConverter.PdfSecurityOptions.EncryptionAlgorithm = rc4RadioButton.Checked ? EncryptionAlgorithm.RC4 : EncryptionAlgorithm.AES;

            // set the encryption key size
            if (bit40RadioButton.Checked)
                htmlToPdfConverter.PdfSecurityOptions.KeySize = EncryptionKeySize.EncryptKey40Bit;
            else if (bit128RadioButton.Checked)
                htmlToPdfConverter.PdfSecurityOptions.KeySize = EncryptionKeySize.EncryptKey128Bit;
            else if (bit256RadioButton.Checked)
                htmlToPdfConverter.PdfSecurityOptions.KeySize = EncryptionKeySize.EncryptKey256Bit;
        }

        // Set user and owner passwords
        if (userPasswordTextBox.Text.Length > 0)
            htmlToPdfConverter.PdfSecurityOptions.UserPassword = userPasswordTextBox.Text;

        if (ownerPasswordTextBox.Text.Length > 0)
            htmlToPdfConverter.PdfSecurityOptions.OwnerPassword = ownerPasswordTextBox.Text;

        // Set PDF document permissions
        htmlToPdfConverter.PdfSecurityOptions.CanPrint = printEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanPrintHighResolution = highResolutionPrintEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanCopyContent = copyContentEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanCopyAccessibilityContent = copyAccessibilityContentEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanEditContent = editContentEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanEditAnnotations = editAnnotationsEnabledCheckBox.Checked;
        htmlToPdfConverter.PdfSecurityOptions.CanFillFormFields = fillFormFieldsEnabledCheckBox.Checked;

        if ((PermissionsChanged(htmlToPdfConverter) || htmlToPdfConverter.PdfSecurityOptions.UserPassword.Length > 0) &&
            htmlToPdfConverter.PdfSecurityOptions.OwnerPassword.Length == 0)
        {
            // A user password is set but the owner password is not set or the permissions are not the default ones
            // Set a default owner password
            htmlToPdfConverter.PdfSecurityOptions.OwnerPassword = "owner";
        }

        Cursor = Cursors.WaitCursor;

        // Convert HTML to PDF using the settings above
        string outPdfFile = @"DemoAppFiles\Output\HTML_to_PDF\Set_Permissions_Password.pdf";
        try
        {
            // Convert the HTML page to a PDF document in a memory buffer
            byte[] outPdfBuffer = htmlToPdfConverter.ConvertUrl(urlTextBox.Text);

            // Write the memory buffer in a PDF file
            System.IO.File.WriteAllBytes(outPdfFile, outPdfBuffer);
        }
        catch (Exception ex)
        {
            // The HTML to PDF conversion failed
            MessageBox.Show(String.Format("HTML to PDF Error. {0}", ex.Message));
            return;
        }
        finally
        {
            Cursor = Cursors.Arrow;
        }

        // Open the created PDF document in default PDF viewer
        try
        {
            System.Diagnostics.Process.Start(outPdfFile);
        }
        catch (Exception ex)
        {
            MessageBox.Show(String.Format("Cannot open created PDF file '{0}'. {1}", outPdfFile, ex.Message));
        }
    }