private void createPdfButton_Click(object sender, EventArgs e)
{
    // Create a PDF document
    Document pdfDocument = new Document();

    // Set license key received after purchase to use the converter in licensed mode
    // Leave it not set to use the converter in demo mode
    pdfDocument.LicenseKey = "fvDh8eDx4fHg4P/h8eLg/+Dj/+jo6Og=";

    // Add a PDF page to PDF document
    PdfPage pdfPage = pdfDocument.AddPage();

    Cursor = Cursors.WaitCursor;

    string outPdfFile = @"DemoAppFiles\Output\PDF_Creator\Change_Header_Footer_Per_Page.pdf";
    HtmlToPdfElement htmlToPdfElement = null;
    try
    {
        // Add a default document header
        AddHeader(pdfDocument, true);

        // Add a default document footer
        AddFooter(pdfDocument, true, true);

        // Create a HTML to PDF element to add to document
        htmlToPdfElement = new HtmlToPdfElement(0, 0, urlTextBox.Text);

        // Optionally set a delay before conversion to allow asynchonous scripts to finish
        htmlToPdfElement.ConversionDelay = 2;
                
        // Install a handler where to change the header and footer in pages generated by the HTML to PDF element
        htmlToPdfElement.PrepareRenderPdfPageEvent += new PrepareRenderPdfPageDelegate(htmlToPdfElement_PrepareRenderPdfPageEvent);

        // Add the HTML to PDF element to document
        // This will raise the PrepareRenderPdfPageEvent event where the header can be changed per page
        pdfPage.AddElement(htmlToPdfElement);

        // 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 PDF creation failed
        MessageBox.Show(String.Format("Create PDF Document Error. {0}", ex.Message));
        return;
    }
    finally
    {
        // uninstall handler
        htmlToPdfElement.PrepareRenderPdfPageEvent -= new PrepareRenderPdfPageDelegate(htmlToPdfElement_PrepareRenderPdfPageEvent);

        // Close the PDF document
        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));
    }
}

/// <summary>
/// The handler for HtmlToPdfElement.PrepareRenderPdfPageEvent event where you can set the visibility of header and footer
/// in each page or you can add a custom header or footer in a page
/// </summary>
/// <param name="eventParams">The event parameter containin the PDF page to customize before rendering</param>
void htmlToPdfElement_PrepareRenderPdfPageEvent(PrepareRenderPdfPageParams eventParams)
{
    if ((eventParams.PageNumber == 1) && changeHeaderAndFooterCheckBox.Checked)
    {
        // Change the header and footer in first page with an alternative header and footer

        // The PDF page being rendered
        PdfPage pdfPage = eventParams.Page;

        // Add a custom header of 80 points in height to this page
        // The default document header will be replaced in this page
        pdfPage.AddHeaderTemplate(80);
        // Draw the page header elements
        DrawAlternativePageHeader(pdfPage.Header, true);

        // Add a custom footer of 80 points in height to this page
        // The default document footer will be replaced in this page
        pdfPage.AddFooterTemplate(80);
        // Draw the page header elements
        DrawAlternativePageFooter(pdfPage.Footer, true, true);
    }
}

/// <summary>
/// Add a header to document
/// </summary>
/// <param name="pdfDocument">The PDF document object</param>
/// <param name="drawHeaderLine">A flag indicating if a line should be drawn at the bottom of the header</param>
private void AddHeader(Document pdfDocument, bool drawHeaderLine)
{
    string headerHtmlUrl = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\HTML_Files\Header_HTML.html");

    // Create the document header template
    pdfDocument.AddHeaderTemplate(60);
            
    // Create a HTML element to be added in header
    HtmlToPdfElement headerHtml = new HtmlToPdfElement(headerHtmlUrl);

    // Set the HTML element to fit the container height
    headerHtml.FitHeight = true;

    // Add HTML element to header
    pdfDocument.Header.AddElement(headerHtml);

    if (drawHeaderLine)
    {
        float headerWidth = pdfDocument.Header.Width;
        float headerHeight = pdfDocument.Header.Height;

        // Create a line element for the bottom of the header
        LineElement headerLine = new LineElement(0, headerHeight - 1, headerWidth, headerHeight - 1);

        // Set line color
        headerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the header
        pdfDocument.Header.AddElement(headerLine);
    }
}

/// <summary>
/// Add a footer to document
/// </summary>
/// <param name="pdfDocument">The PDF document object</param>
/// <param name="addPageNumbers">A flag indicating if the page numbering is present in footer</param>
/// <param name="drawFooterLine">A flag indicating if a line should be drawn at the top of the footer</param>
private void AddFooter(Document pdfDocument, bool addPageNumbers, bool drawFooterLine)
{
    string footerHtmlUrl = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\HTML_Files\Footer_HTML.html");

    // Create the document footer template
    pdfDocument.AddFooterTemplate(60);

    // Set footer background color
    RectangleElement backColorRectangle = new RectangleElement(0, 0, pdfDocument.Footer.Width, pdfDocument.Footer.Height);
    backColorRectangle.BackColor = Color.WhiteSmoke;
    pdfDocument.Footer.AddElement(backColorRectangle);

    // Create a HTML element to be added in footer
    HtmlToPdfElement footerHtml = new HtmlToPdfElement(footerHtmlUrl);

    // Set the HTML element to fit the container height
    footerHtml.FitHeight = true;

    // Add HTML element to footer
    pdfDocument.Footer.AddElement(footerHtml);

    // Add page numbering
    if (addPageNumbers)
    {
        // Create a text element with page numbering place holders &p; and & P;
        TextElement footerText = new TextElement(0, 30, "Page &p; of &P;  ",
            new System.Drawing.Font(new System.Drawing.FontFamily("Times New Roman"), 10, System.Drawing.GraphicsUnit.Point));

        // Align the text at the right of the footer
        footerText.TextAlign = HorizontalTextAlign.Right;

        // Set page numbering text color
        footerText.ForeColor = Color.Navy;

        // Embed the text element font in PDF
        footerText.EmbedSysFont = true;

        // Add the text element to footer
        pdfDocument.Footer.AddElement(footerText);
    }

    if (drawFooterLine)
    {
        float footerWidth = pdfDocument.Footer.Width;

        // Create a line element for the top of the footer
        LineElement footerLine = new LineElement(0, 0, footerWidth, 0);

        // Set line color
        footerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the footer
        pdfDocument.Footer.AddElement(footerLine);
    }
}

/// <summary>
/// Draw the alternative page header elements
/// </summary>
/// <param name="headerTemplate">The page header template</param>
/// <param name="drawHeaderLine">A flag indicating if a line should be drawn at the bottom of the header</param>
private void DrawAlternativePageHeader(Template headerTemplate, bool drawHeaderLine)
{
    string headerHtmlUrl = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\HTML_Files\Header_Alt_HTML.html");

    // Create a HTML element to be added in header
    HtmlToPdfElement headerHtml = new HtmlToPdfElement(headerHtmlUrl);

    // Set the HTML element to fit the container height
    headerHtml.FitHeight = true;

    // Add HTML element to header
    headerTemplate.AddElement(headerHtml);

    if (drawHeaderLine)
    {
        float headerWidth = headerTemplate.Width;
        float headerHeight = headerTemplate.Height;

        // Create a line element for the bottom of the header
        LineElement headerLine = new LineElement(0, headerHeight - 1, headerWidth, headerHeight - 1);

        // Set line color
        headerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the header
        headerTemplate.AddElement(headerLine);
    }
}

/// <summary>
/// Draw the alternative page footer elements
/// </summary>
/// <param name="htmlToPdfConverter">The HTML to PDF Converter object</param>
/// <param name="addPageNumbers">A flag indicating if the page numbering is present in footer</param>
/// <param name="drawFooterLine">A flag indicating if a line should be drawn at the top of the footer</param>
private void DrawAlternativePageFooter(Template footerTemplate, bool addPageNumbers, bool drawFooterLine)
{
    string footerHtmlUrl = System.IO.Path.Combine(Application.StartupPath,
                @"DemoAppFiles\Input\HTML_Files\Footer_Alt_HTML.html");

    // Create a HTML element to be added in footer
    HtmlToPdfElement footerHtml = new HtmlToPdfElement(footerHtmlUrl);

    // Set the HTML element to fit the container height
    footerHtml.FitHeight = true;

    // Add HTML element to footer
    footerTemplate.AddElement(footerHtml);

    // Add page numbering
    if (addPageNumbers)
    {
        // Create a text element with page numbering place holders &p; and & P;
        TextElement footerText = new TextElement(10, 30, "Page &p; of &P;",
            new System.Drawing.Font(new System.Drawing.FontFamily("Times New Roman"), 10, System.Drawing.GraphicsUnit.Point));

        // Align the text at the right of the footer
        footerText.TextAlign = HorizontalTextAlign.Left;

        // Set page numbering text color
        footerText.ForeColor = Color.Navy;

        // Embed the text element font in PDF
        footerText.EmbedSysFont = true;

        // Add the text element to footer
        footerTemplate.AddElement(footerText);
    }

    if (drawFooterLine)
    {
        float footerWidth = footerTemplate.Width;

        // Create a line element for the top of the footer
        LineElement footerLine = new LineElement(0, 0, footerWidth, 0);

        // Set line color
        footerLine.ForeColor = Color.Gray;

        // Add line element to the bottom of the footer
        footerTemplate.AddElement(footerLine);
    }
}