Merge Multiple HTML Pages into a Single PDF

protected void convertToPdfButton_Click(object sender, EventArgs e)
{
    // Create the PDF document where to add the HTML documents
    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 = "4W9+bn19bn5ue2B+bn1/YH98YHd3d3c=";

    // Create a PDF page where to add the first HTML
    PdfPage firstPdfPage = pdfDocument.AddPage();

    try
    {
        // Create the first HTML to PDF element
        HtmlToPdfElement firstHtml = new HtmlToPdfElement(0, 0, firstUrlTextBox.Text);

        // Optionally set a delay before conversion to allow asynchonous scripts to finish
        firstHtml.ConversionDelay = 2;

        // Add the first HTML to PDF document
        AddElementResult firstAddResult = firstPdfPage.AddElement(firstHtml);

        PdfPage secondPdfPage = null;
        PointF secondHtmlLocation = Point.Empty;

        if (startNewPageCheckBox.Checked)
        {
            // Create a PDF page where to add the second HTML
            secondPdfPage = pdfDocument.AddPage();
            secondHtmlLocation = PointF.Empty;
        }
        else
        {
            // Add the second HTML on the PDF page where the first HTML ended
            secondPdfPage = firstAddResult.EndPdfPage;
            secondHtmlLocation = new PointF(firstAddResult.EndPageBounds.Left, firstAddResult.EndPageBounds.Bottom);
        }

        // Create the second HTML to PDF element
        HtmlToPdfElement secondHtml = new HtmlToPdfElement(secondHtmlLocation.X, secondHtmlLocation.Y, secondUrlTextBox.Text);

        // Optionally set a delay before conversion to allow asynchonous scripts to finish
        secondHtml.ConversionDelay = 2;

        // Add the second HTML to PDF document
        secondPdfPage.AddElement(secondHtml);

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

        // Send the PDF as response to browser

        // Set response content type
        Response.AddHeader("Content-Type", "application/pdf");

        // Instruct the browser to open the PDF file as an attachment or inline
        Response.AddHeader("Content-Disposition", String.Format("attachment; filename=Merge_Multipe_HTML.pdf; size={0}", outPdfBuffer.Length.ToString()));

        // Write the PDF document buffer to HTTP response
        Response.BinaryWrite(outPdfBuffer);

        // End the HTTP response and stop the current page processing
        Response.End();
    }
    finally
    {
        // Close the PDF document
        pdfDocument.Close();
    }
}

Protected Sub convertToPdfButton_Click(ByVal sender As Object, ByVal e As EventArgs)
    ' Create the PDF document where to add the HTML documents
    Dim pdfDocument As 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 = "4W9+bn19bn5ue2B+bn1/YH98YHd3d3c="

    ' Create a PDF page where to add the first HTML
    Dim firstPdfPage As PdfPage = pdfDocument.AddPage()

    Try
        ' Create the first HTML to PDF element
        Dim firstHtml As New HtmlToPdfElement(0, 0, firstUrlTextBox.Text)

        ' Optionally set a delay before conversion to allow asynchonous scripts to finish
        firstHtml.ConversionDelay = 2

        ' Add the first HTML to PDF document
        Dim firstAddResult As AddElementResult = firstPdfPage.AddElement(firstHtml)

        Dim secondPdfPage As PdfPage = Nothing
        Dim secondHtmlLocation As PointF = Point.Empty

        If startNewPageCheckBox.Checked Then
            ' Create a PDF page where to add the second HTML
            secondPdfPage = pdfDocument.AddPage()
            secondHtmlLocation = PointF.Empty
        Else
            ' Add the second HTML on the PDF page where the first HTML ended
            secondPdfPage = firstAddResult.EndPdfPage
            secondHtmlLocation = New PointF(firstAddResult.EndPageBounds.Left, firstAddResult.EndPageBounds.Bottom)
        End If

        ' Create the second HTML to PDF element
        Dim secondHtml As New HtmlToPdfElement(secondHtmlLocation.X, secondHtmlLocation.Y, secondUrlTextBox.Text)

        ' Optionally set a delay before conversion to allow asynchonous scripts to finish
        secondHtml.ConversionDelay = 2

        ' Add the second HTML to PDF document
        secondPdfPage.AddElement(secondHtml)

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

        ' Send the PDF as response to browser

        ' Set response content type
        Response.AddHeader("Content-Type", "application/pdf")

        ' Instruct the browser to open the PDF file as an attachment or inline
        Response.AddHeader("Content-Disposition", String.Format("attachment; filename=Merge_Multipe_HTML.pdf; size={0}", outPdfBuffer.Length.ToString()))

        ' Write the PDF document buffer to HTTP response
        Response.BinaryWrite(outPdfBuffer)

        ' End the HTTP response and stop the current page processing
        Response.End()
    Finally
        ' Close the PDF document
        pdfDocument.Close()
    End Try
End Sub