Select in HTML the Elements for Which to Retrieve Information

using System;
using System.Collections.Generic;
using System.Linq;
using System.Threading.Tasks;
using Microsoft.AspNetCore.Mvc;
using Microsoft.AspNetCore.Http;

using System.Text;

// Use EVO PDF Namespace
using EvoPdfClient;

namespace EvoHtmlToPdfDemo.Controllers.HTML_to_PDF.HTML_Elements_Location
{
    public class Select_in_HTML_Elements_to_RetrieveController : Controller
    {
        [HttpPost]
        public ActionResult ConvertHtmlToPdf(IFormCollection collection)
        {
            // Get the server options
            string serverIP = collection["textBoxServerIP"];
            uint serverPort = uint.Parse(collection["textBoxServerPort"]);
            string servicePassword = collection["textBoxServicePassword"];
            bool useServicePassword = servicePassword.Length > 0;
            bool useTcpService = collection["ServerType"] == "radioButtonUseTcpService";
            string webServiceUrl = collection["textBoxWebServiceUrl"];

            // Create the HTML to PDF converter object
            HtmlToPdfConverter htmlToPdfConverter = null;
            if (useTcpService)
                htmlToPdfConverter = new HtmlToPdfConverter(serverIP, serverPort);
            else
                htmlToPdfConverter = new HtmlToPdfConverter(true, webServiceUrl);

            // Set optional service password
            if (useServicePassword)
                htmlToPdfConverter.ServicePassword = servicePassword;

            // 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;

            Document pdfDocument = null;

            // Convert HTML page or string with mapping attributes to a PDF document object 
            // The document can be further modified to highlight the selected elements
            if (collection["HtmlPageSource"] == "convertHtmlRadioButton")
            {
                string htmlWithMappingAttributes = collection["htmlStringTextBox"];
                string baseUrl = collection["baseUrlTextBox"];

                // Convert a HTML string with mapping attributes to a PDF document object
                pdfDocument = htmlToPdfConverter.ConvertHtmlToPdfDocumentObject(htmlWithMappingAttributes, baseUrl);
            }
            else
            {
                string url = collection["urlTextBox"];

                // Convert a HTML page with mapping attributes to a PDF document object
                pdfDocument = htmlToPdfConverter.ConvertUrlToPdfDocumentObject(url);
            }

            // Display detailed information about the selected elements
            StringBuilder htmlElementInfoBuilder = new StringBuilder();
            for (int mappingIndex = 0; mappingIndex < htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.Count; mappingIndex++)
            {
                HtmlElementMapping htmlElementInfo = htmlToPdfConverter.HtmlElementsMappingOptions.HtmlElementsMappingResult.GetByIndex(mappingIndex);

                // Get other information about HTML element
                string htmlElementTagName = htmlElementInfo.HtmlElementTagName;
                string htmlElementID = htmlElementInfo.HtmlElementId;
                string htmlElementMappingID = htmlElementInfo.MappingId;
                string htmlElementCssClasssName = htmlElementInfo.HtmlElementCssClassName;
                string htmlElementHtmlCode = htmlElementInfo.HtmlElementOuterHtml;
                string htmlElementInnerHtml = htmlElementInfo.HtmlElementInnerHtml;
                string htmlElementText = htmlElementInfo.HtmlElementText;
                NameValuePairsCollection htmlElementAttributes = htmlElementInfo.HtmlElementAttributes;
                PdfRectangle[] htmlElementRectanglesInPdf = htmlElementInfo.PdfRectangles;

                htmlElementInfoBuilder.AppendFormat("<br/>---------------------------------------- HTML Element Info ----------------------------------------<br/><br/>");
                htmlElementInfoBuilder.AppendFormat("<b>Tag Name:</b> {0}<br/>", htmlElementTagName);
                htmlElementInfoBuilder.AppendFormat("<b>Element ID:</b> {0}<br/>", htmlElementID);
                htmlElementInfoBuilder.AppendFormat("<b>Mapping ID:</b> {0}<br/>", htmlElementMappingID);
                htmlElementInfoBuilder.AppendFormat("<b>Text:</b> {0}<br/>", htmlElementText);

                htmlElementInfoBuilder.AppendFormat("<b>Attributes:</b><br/>");
                for (int i = 0; i < htmlElementAttributes.Count; i++)
                {
                    NameValuePair nameValuePair = htmlElementAttributes.GetByIndex(i);
                    htmlElementInfoBuilder.AppendFormat("&nbsp;&nbsp;&nbsp;{0} = \"{1}\"<br/>", nameValuePair.Name, nameValuePair.Value);
                }


                htmlElementInfoBuilder.AppendFormat("<b>Location in PDF:</b><br/>");
                for (int i = 0; i < htmlElementRectanglesInPdf.Length; i++)
                {
                    PdfPage pdfPage = pdfDocument.GetPage(htmlElementRectanglesInPdf[i].PageIndex);
                    int pdfPageIndex = htmlElementRectanglesInPdf[i].PageIndex;
                    RectangleFloat rectangleInPdfPage = htmlElementRectanglesInPdf[i].Rectangle;

                    htmlElementInfoBuilder.AppendFormat("&nbsp;&nbsp;&nbsp;PDF Page Index: {0}<br>", pdfPageIndex);
                    htmlElementInfoBuilder.AppendFormat("&nbsp;&nbsp;&nbsp;Rectangle: X = {0:N2} pt , Y = {1:N2} pt , W = {2:N2} pt , H = {3:N2} pt<br/>",
                            rectangleInPdfPage.X, rectangleInPdfPage.Y, rectangleInPdfPage.Width, rectangleInPdfPage.Height);
                }

                htmlElementInfoBuilder.AppendFormat("<br/>");
            }

            PdfPage lastPdfPage = pdfDocument.GetPage(htmlToPdfConverter.ConversionSummary.LastPageIndex);
            RectangleFloat lastPageRectangle = htmlToPdfConverter.ConversionSummary.LastPageRectangle;

            HtmlToPdfElement htmlElementInfoHtml = new HtmlToPdfElement(0, lastPageRectangle.Y + lastPageRectangle.Height + 1, htmlElementInfoBuilder.ToString(), null);
            lastPdfPage.AddElement(htmlElementInfoHtml);

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

            // Send the PDF file to browser
            FileResult fileResult = new FileContentResult(outPdfBuffer, "application/pdf");
            fileResult.FileDownloadName = "Select_in_HTML_Elements_to_Retrieve.pdf";

            return fileResult;
        }
    }
}

<!DOCTYPE html>
<html>
<head>
    <title>Select in HTML the Elements for Which to Retrieve Information</title>
</head>
<body style="font-family: 'Times New Roman'; font-size: 14px">
    <span style="font-size: 24px; font-weight: bold; color: navy">Select the HTML Elements Using 'Data-Mapping-Enabled' Attribute</span><br />
    <br />
    <span style="font-size: 14px; color: black">Detailed information about the following elements will be retrieved and displayed right in the generated PDF:
    </span>
    <br />
    <br />
    <!-- HTML elements for which to retrieve detailed information -->
    <img data-mapping-enabled="true" data-mapping-id="logo_image" alt="Logo Image" style="width: 350px" src="img/logo.jpg" id="imageHtmlID" />
    <br />
    <br />
    <a data-mapping-enabled="true" data-mapping-id="link_to_website" style="font-size: 18px; font-weight: bold; color: navy" href="http://www.evopdf.com" id="linkHtmlID">Visit EVO HTML to PDF Converter Website</a>
</body>
</html>