    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;

        Cursor = Cursors.WaitCursor;

        // Convert HTML to PDF using the settings above
        string outPdfFile = @"DemoAppFiles\Output\HTML_to_PDF\File_Links_and_Attachments.pdf";
        Document pdfDocument = null;
        try
        {
            string htmlWithLinksAndAttachMarkers = htmlStringTextBox.Text;
            string baseUrl = baseUrlTextBox.Text;

            // Convert a HTML string with markers for file links and attachments to a PDF document object
            pdfDocument = htmlToPdfConverter.ConvertHtmlToPdfDocumentObject(htmlWithLinksAndAttachMarkers, baseUrl);

            // Display the attachments panel when the PDF document is opened in a PDF viewer
            pdfDocument.ViewerPreferences.PageMode = ViewerPageMode.UseAttachments;

            // Create File Links

            // Make the HTML element with 'file_link_text' mapping ID a link to an external file
            HtmlElementMapping fileLinkTextMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("file_link_text");
            if (fileLinkTextMapping != null)
            {
                PdfPage fileLinkTextPage = fileLinkTextMapping.PdfRectangles[0].PdfPage;
                RectangleF fileLinkTextRectangle = fileLinkTextMapping.PdfRectangles[0].Rectangle;

                string filePath = @"..\..\Input\Attach_Files\Linked_External_File.txt";

                // Create the file link
                FileLinkElement fileLinkTextElement = new FileLinkElement(fileLinkTextRectangle, filePath);
                fileLinkTextPage.AddElement(fileLinkTextElement);
            }

            // Make the HTML element with 'file_link_img' ID a link to an external file
            HtmlElementMapping fileLinkImgMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("file_link_image");
            if (fileLinkImgMapping != null)
            {
                PdfPage fileLinkImgPage = fileLinkImgMapping.PdfRectangles[0].PdfPage;
                RectangleF fileLinkImgRectangle = fileLinkImgMapping.PdfRectangles[0].Rectangle;

                string filePath = @"..\..\Input\Attach_Files\Linked_External_File.txt";

                // Create the file link
                FileLinkElement fileLinkImgElement = new FileLinkElement(fileLinkImgRectangle, filePath);
                fileLinkImgPage.AddElement(fileLinkImgElement);
            }

            // Create File Attachments

            // Create an attachment from a file without icon
            string fileAttachmentPath = @"DemoAppFiles\Input\Attach_Files\Attachment_File.txt";
            pdfDocument.AddFileAttachment(fileAttachmentPath, "Attachment from File");

            // Create an attachment from a stream without icon
            string fileStreamAttachmentPath = @"DemoAppFiles\Input\Attach_Files\Attachment_Stream.txt";
            System.IO.FileStream attachmentStream = new System.IO.FileStream(fileStreamAttachmentPath, System.IO.FileMode.Open, System.IO.FileAccess.Read);
            pdfDocument.AddFileAttachment(attachmentStream, "Attachment_Stream.txt", "Attachment from Stream");

            // Create an attachment from file with paperclip icon in PDF
            HtmlElementMapping attachFromFileIconMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("attach_from_file_icon");
            if (attachFromFileIconMapping != null)
            {
                PdfPage attachFromFilePage = attachFromFileIconMapping.PdfRectangles[0].PdfPage;
                RectangleF attachFromFileIconRectangle = attachFromFileIconMapping.PdfRectangles[0].Rectangle;

                string fileAttachmentWithIconPath = @"DemoAppFiles\Input\Attach_Files\Attachment_File_Icon.txt";

                // Create the attachment from file
                FileAttachmentElement attachFromFileElement = new FileAttachmentElement(attachFromFileIconRectangle, fileAttachmentWithIconPath);
                attachFromFileElement.IconType = FileAttachmentIcon.Paperclip;
                attachFromFileElement.Text = "Attachment from File with Paperclip Icon";
                attachFromFileElement.IconColor = Color.Blue;
                attachFromFilePage.AddElement(attachFromFileElement);
            }

            // Create an attachment from stream with pushpin icon in PDF
            System.IO.FileStream attachmentStreamWithIcon = null;
            HtmlElementMapping attachFromStreamIconMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("attach_from_stream_icon");
            if (attachFromStreamIconMapping != null)
            {
                PdfPage attachFromStreamPage = attachFromStreamIconMapping.PdfRectangles[0].PdfPage;
                RectangleF attachFromStreamIconRectangle = attachFromStreamIconMapping.PdfRectangles[0].Rectangle;

                string fileStreamAttachmentWithIconPath = @"DemoAppFiles\Input\Attach_Files\Attachment_Stream_Icon.txt";

                attachmentStreamWithIcon = new System.IO.FileStream(fileStreamAttachmentWithIconPath, System.IO.FileMode.Open, System.IO.FileAccess.Read);

                // Create the attachment from stream
                FileAttachmentElement attachFromStreamElement = new FileAttachmentElement(attachFromStreamIconRectangle, attachmentStreamWithIcon, "Attachment_Stream_Icon.txt");
                attachFromStreamElement.IconType = FileAttachmentIcon.PushPin;
                attachFromStreamElement.Text = "Attachment from Stream with Pushpin Icon";
                attachFromStreamElement.IconColor = Color.Green;
                attachFromStreamPage.AddElement(attachFromStreamElement);
            }

            // Save the PDF document in a memory buffer
            byte[] outPdfBuffer = pdfDocument.Save();

            // 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
        {
            // Close the PDF document
            if (pdfDocument != null)
                pdfDocument.Close();

            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));
        }
    }