    using System;
    using System.Collections.Generic;
    using System.Web;
    using System.Web.UI;
    using System.Web.UI.WebControls;

    using System.Drawing;

    // Use EVO PDF Namespace
    using EvoPdfClient;

    namespace EvoHtmlToPdfDemo.HTML_to_PDF.HTML_Elements_Location
    {
        public partial class Select_in_API_Elements_to_Retrieve : System.Web.UI.Page
        {
            protected void convertToPdfButton_Click(object sender, EventArgs e)
            {
                // Get the server IP and port
                String serverIP = textBoxServerIP.Text;
                uint serverPort = uint.Parse(textBoxServerPort.Text);

                // Create a HTML to PDF converter object
                HtmlToPdfConverter htmlToPdfConverter = null;
                if (radioButtonUseTcpService.Checked)
                    htmlToPdfConverter = new HtmlToPdfConverter(serverIP, serverPort);
                else
                    htmlToPdfConverter = new HtmlToPdfConverter(true, textBoxWebServiceUrl.Text);

                // Set optional service password
                if (textBoxServicePassword.Text.Length > 0)
                    htmlToPdfConverter.ServicePassword = textBoxServicePassword.Text;

                // 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;

                // Select the HTML elements for which to retrieve location and other information from HTML document
                htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementSelectors = new string[] { htmlElementsSelectorTextBox.Text };

                // Convert HTML page to a PDF document object which can be further modified to highlight the selected elements
                Document pdfDocument = htmlToPdfConverter.ConvertUrlToPdfDocumentObject(urlTextBox.Text);

                // Highlight the selected elements in PDF with colored rectangles
                for (int i = 0; i < htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.Count; i++)
                {
                    HtmlElementMapping htmlElementInfo = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetByIndex(i);
                    // Get other information about HTML element
                    string htmlElementTagName = htmlElementInfo.HtmlElementTagName;
                    string htmlElementID = htmlElementInfo.HtmlElementId;

                    // Hightlight the HTML element in PDF

                    // A HTML element can span over many PDF pages and therefore the mapping of the HTML element in PDF document consists
                    // in a list of rectangles, one rectangle for each PDF page where this element was rendered
                    foreach (PdfRectangle htmlElementLocationInPdf in htmlElementInfo.PdfRectangles)
                    {
                        // Get the HTML element location in PDF page
                        PdfPage htmlElementPdfPage = pdfDocument.GetPage(htmlElementLocationInPdf.PageIndex);
                        RectangleFloat htmlElementRectangleInPdfPage = htmlElementLocationInPdf.Rectangle;

                        // Highlight the HTML element element with a colored rectangle in PDF
                        RectangleElement highlightRectangle = new RectangleElement(htmlElementRectangleInPdfPage.X, htmlElementRectangleInPdfPage.Y,
                            htmlElementRectangleInPdfPage.Width, htmlElementRectangleInPdfPage.Height);

                        if (htmlElementTagName.ToLower() == "h1")
                            highlightRectangle.ForeColor = RgbColor.Blue;
                        else if (htmlElementTagName.ToLower() == "h2")
                            highlightRectangle.ForeColor = RgbColor.Green;
                        else if (htmlElementTagName.ToLower() == "h3")
                            highlightRectangle.ForeColor = RgbColor.Red;
                        else if (htmlElementTagName.ToLower() == "h4")
                            highlightRectangle.ForeColor = RgbColor.Yellow;
                        else if (htmlElementTagName.ToLower() == "h5")
                            highlightRectangle.ForeColor = RgbColor.Indigo;
                        else if (htmlElementTagName.ToLower() == "h6")
                            highlightRectangle.ForeColor = RgbColor.Orange;
                        else
                            highlightRectangle.ForeColor = RgbColor.Navy;

                        highlightRectangle.LineStyle.LineDashStyle = LineDashStyle.Solid;

                        htmlElementPdfPage.AddElement(highlightRectangle);
                    }
                }

                // 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=Select_in_API_HTML_Elements_to_Retrieve.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();
            }

            protected void Page_Load(object sender, EventArgs e)
            {
                if (!IsPostBack)
                {
                    sampleCodeLiteral.Text = System.IO.File.ReadAllText(Server.MapPath("~/DemoAppFiles/Input/Code_Samples/CSharp/AspNet/HTML_to_PDF/HTML_Elements_Location/Select_in_API.html"));
                    descriptionLiteral.Text = System.IO.File.ReadAllText(Server.MapPath("~/DemoAppFiles/Input/Descriptions/AspNet/HTML_to_PDF/HTML_Elements_Location/Select_in_API.html"));

                    Master.CollapseAll();
                    Master.ExpandNode("HTML_to_PDF");
                    Master.ExpandNode("HTML_Elements_Location_in_PDF");
                    Master.SelectNode("Select_in_API_Elements_to_Retrieve");
                }
            }

            protected void demoMenu_MenuItemClick(object sender, MenuEventArgs e)
            {
                switch (e.Item.Value)
                {
                    case "Live_Demo":
                        demoMultiView.SetActiveView(liveDemoView);
                        break;
                    case "Description":
                        demoMultiView.SetActiveView(descriptionView);
                        break;
                    case "Sample_Code":
                        demoMultiView.SetActiveView(sampleCodeView);
                        break;
                    default:
                        break;
                }
            }
        }
    }