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 = "fvDh8eDx4fHg4P/h8eLg/+Dj/+jo6Og="

    ' Select all images from HTML page
    htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementSelectors = New String() {"img"}

    ' Exclude the original images from rendering becuase they will be replaced by an image from local file system
    htmlToPdfConverter.HiddenHtmlElementsSelectors = New String() {"img"}

    Cursor = Cursors.WaitCursor

    Dim outPdfFile As String = "DemoAppFiles\Output\HTML_to_PDF\Replace_with_Higher_Quality_Images.pdf"
    Dim pdfDocument As Document = Nothing
    Try
        ' Convert a HTML string with images to replace to a PDF document object
        pdfDocument = htmlToPdfConverter.ConvertUrlToPdfDocumentObject(urlTextBox.Text)

        ' Replace the images selected in HTML using special attributes with images from local file system
        For Each imageElementInfo As HtmlElementMapping In htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult
            Dim imagePdfPage As PdfPage = imageElementInfo.PdfRectangles(0).PdfPage
            Dim imageRectangle As RectangleF = imageElementInfo.PdfRectangles(0).Rectangle

            Dim newImageElement As New ImageElement(imageRectangle.X, imageRectangle.Y, imageRectangle.Width, imageRectangle.Height, "DemoAppFiles\Input\Images\box.jpg")
            newImageElement.EnlargeEnabled = True
            imagePdfPage.AddElement(newImageElement)
        Next imageElementInfo

        ' 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