Add File Links and Attachments to Generated PDF Document

EVO HTML to PDF Converter for .NET Documentation

EVO HTML to PDF Converter allows you to create relative or absolute file links in PDF and to create file attachments from files or from streams. Optionally you can also add icons to mark the attachments in PDF document. In this demo some of the HTML elements from converted PDF document are marked to become links to files or icons for attachments in the generated PDF document.

The file links are created by adding FileLinkElement objects to a PDF document and the file attachments are created by adding FileAttachmentElement objects to a PDF document when the attachment is marked by an icon in the generated PDF document or by using the DocumentAddFileAttachment(String, String) method when the attachment does not need an icon in the generated PDF document.

Code Sample - Add File Links and Attachments to Generated PDF Document

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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));
    }
}

Private Sub convertToPdfButton_Click(ByVal sender As Object, ByVal e As EventArgs) Handles convertToPdfButton.Click
    ' Create a HTML to PDF converter object with default settings
    Dim htmlToPdfConverter As 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
    Dim outPdfFile As String = "DemoAppFiles\Output\HTML_to_PDF\File_Links_and_Attachments.pdf"
    Dim pdfDocument As Document = Nothing
    Try
        Dim htmlWithLinksAndAttachMarkers As String = htmlStringTextBox.Text
        Dim baseUrl As String = 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
        Dim fileLinkTextMapping As HtmlElementMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("file_link_text")
        If fileLinkTextMapping IsNot Nothing Then
            Dim fileLinkTextPage As PdfPage = fileLinkTextMapping.PdfRectangles(0).PdfPage
            Dim fileLinkTextRectangle As RectangleF = fileLinkTextMapping.PdfRectangles(0).Rectangle

            Dim filePath As String = "..\..\Input\Linked_Files\Linked_External_File.txt"

            ' Create the file link
            Dim fileLinkTextElement As New FileLinkElement(fileLinkTextRectangle, filePath)
            fileLinkTextPage.AddElement(fileLinkTextElement)
        End If

        ' Make the HTML element with 'file_link_img' ID a link to an external file
        Dim fileLinkImgMapping As HtmlElementMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("file_link_image")
        If fileLinkImgMapping IsNot Nothing Then
            Dim fileLinkImgPage As PdfPage = fileLinkImgMapping.PdfRectangles(0).PdfPage
            Dim fileLinkImgRectangle As RectangleF = fileLinkImgMapping.PdfRectangles(0).Rectangle

            Dim filePath As String = "..\..\Input\Linked_Files\Linked_External_File.txt"

            ' Create the file link
            Dim fileLinkImgElement As New FileLinkElement(fileLinkImgRectangle, filePath)
            fileLinkImgPage.AddElement(fileLinkImgElement)
        End If

        ' Create File Attachments

        ' Create an attachment from a file without icon
        Dim fileAttachmentPath As String = "DemoAppFiles\Input\Attach_Files\Attachment_File.txt"
        pdfDocument.AddFileAttachment(fileAttachmentPath, "Attachment from File")

        ' Create an attachment from a stream without icon
        Dim fileStreamAttachmentPath As String = "DemoAppFiles\Input\Attach_Files\Attachment_Stream.txt"
        Dim attachmentStream As 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
        Dim attachFromFileIconMapping As HtmlElementMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("attach_from_file_icon")
        If attachFromFileIconMapping IsNot Nothing Then
            Dim attachFromFilePage As PdfPage = attachFromFileIconMapping.PdfRectangles(0).PdfPage
            Dim attachFromFileIconRectangle As RectangleF = attachFromFileIconMapping.PdfRectangles(0).Rectangle

            Dim fileAttachmentWithIconPath As String = "DemoAppFiles\Input\Attach_Files\Attachment_File_Icon.txt"

            ' Create the attachment from file
            Dim attachFromFileElement As New FileAttachmentElement(attachFromFileIconRectangle, fileAttachmentWithIconPath)
            attachFromFileElement.IconType = FileAttachmentIcon.Paperclip
            attachFromFileElement.Text = "Attachment from File with Paperclip Icon"
            attachFromFileElement.IconColor = Color.Blue
            attachFromFilePage.AddElement(attachFromFileElement)
        End If

        ' Create an attachment from stream with pushpin icon in PDF
        Dim attachmentStreamWithIcon As System.IO.FileStream = Nothing
        Dim attachFromStreamIconMapping As HtmlElementMapping = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetElementByMappingId("attach_from_stream_icon")
        If attachFromStreamIconMapping IsNot Nothing Then
            Dim attachFromStreamPage As PdfPage = attachFromStreamIconMapping.PdfRectangles(0).PdfPage
            Dim attachFromStreamIconRectangle As RectangleF = attachFromStreamIconMapping.PdfRectangles(0).Rectangle

            Dim fileStreamAttachmentWithIconPath As String = "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
            Dim attachFromStreamElement As 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)
        End If

        ' Save the PDF document in a memory buffer
        Dim outPdfBuffer() As Byte = pdfDocument.Save()

        ' Write the memory buffer in a PDF file
        System.IO.File.WriteAllBytes(outPdfFile, outPdfBuffer)
    Catch ex As Exception
        ' 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 IsNot Nothing Then
            pdfDocument.Close()
        End If

        Cursor = Cursors.Arrow
    End Try

    ' Open the created PDF document in default PDF viewer
    Try
        Process.Start(outPdfFile)
    Catch ex As Exception
        MessageBox.Show(String.Format("Cannot open created PDF file '{0}'. {1}", outPdfFile, ex.Message))
    End Try
End Sub

HTML Code with Markers for File Links and Attachments

XML

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<!DOCTYPE html>
<html>
<head>
    <title>Add File Links and Attachments to PDF</title>
</head>
<body style="font-family: 'Times New Roman'; font-size: 14px">
    <span style="font-size: 24px; font-weight: bold">File Links</span><br />
    <br />
    <span>The image and the text below will become links to a file from disk:</span>
    <br />
    <br />
    <span data-mapping-enabled="true" data-mapping-id="file_link_text" style="font-size: 16px; font-weight: bold; text-decoration: underline; color: navy">Click to open the external file</span><br />
    <br />
    <img data-mapping-enabled="true" data-mapping-id="file_link_image" alt="Logo Image" style="width: 200px" src="img/logo.jpg" />
    <br />
    <br />
    <span style="font-size: 24px; font-weight: bold">File Attachments</span><br />
    <br />
    <span style="">Click the next icon to open the attachment from a file:</span>
    <span data-mapping-enabled="true" data-mapping-id="attach_from_file_icon">&nbsp;&nbsp;</span><br />
    <br />
    <span style="">Click the next icon to open the attachment from a stream:</span>
    <span data-mapping-enabled="true" data-mapping-id="attach_from_stream_icon">&nbsp;&nbsp;</span><br />
    <br />
</body>
</html>