Task #1068: Using custom ImageDevice

using System;
using Aspose.Html.Dom;
using Aspose.Html.IO;
using Aspose.Html.Rendering.Image;
using Aspose.Html.Drawing;
using Aspose.Html;
using Aspose.Html.Rendering;
using System.Diagnostics;
using System.IO;

namespace Task1068
{
    class Program
    {
        private static HTMLDocument _document=new HTMLDocument();
        static void Main()
        {
            GenerateSampleHtml5Document();
            RenderSimpleExample(@"C:\Aspose\files\filter_h1.jpg");
        }

        private static void RenderSimpleExample(string outputImgFile)
        {
            var imgOptions = new ImageRenderingOptions
            {
                Format = ImageFormat.Jpeg,
                PageSetup =
                {
                    AnyPage = new Page(new Aspose.Html.Drawing.Size(Unit.FromPixels(1366),Unit.FromPixels(768)))
                }
            };

        var imgDevice = new MyImageDevice(imgOptions, outputImgFile);
        var renderer = new HtmlRenderer();

        Console.WriteLine("Render JPG file started...");
            renderer.Render(imgDevice, _document);
            Console.WriteLine("Render JPG file finished.");
        }

    private static void GenerateSampleHtml5Document()
        {
            _document.InsertBefore(_document.CreateDocumentType("html", "", "", ""), _document.DocumentElement);
            _document.DocumentElement.SetAttribute("lang", "en");
            _document.Title = "Page for IMG rendering demo";

            var head = _document.GetElementsByTagName("head")[0];
            var metaCharSet = (HTMLMetaElement)_document.CreateElement("meta");
            metaCharSet.SetAttribute("charset", "UTF-8");

            var metaViewPort = (HTMLMetaElement)_document.CreateElement("meta");
            metaViewPort.Name = "viewport";
            metaViewPort.Content = "width=device-width, initial-scale=1";

            var linkElement1 = (HTMLLinkElement)_document.CreateElement("link");
            linkElement1.Href = "http://cdn.myunv.com/css/uecore.css";
            linkElement1.Rel = "stylesheet";

            var linkElement2 = (HTMLLinkElement)_document.CreateElement("link");
            //linkElement2.Href = "https://fonts.googleapis.com/css?family=Germania+One";
            linkElement2.Href = "https://fonts.googleapis.com/css?family=Merriweather|Roboto+Slab";
            linkElement2.Rel = "stylesheet";

            var style = (HTMLStyleElement)_document.CreateElement("style");
            //style.TextContent = "h1 {color: red;} h2 {color:green} table { border: 1px dashed black}" +
            //    "h2 {page-break-after: always; } p {font-family: 'Germania One', cursive;}" + "@page { size: 7in 9.25in; margin: 27mm 16mm 27mm 16mm; }";
            style.TextContent = "h1 {color: red; font-family: 'Roboto Slab', serif;}" +
                                "h2 {color:green} " +
                                "table { border: 1px dashed black}" +
                                "p {font-family: 'Merriweather', serif;}";
            //"p {font-family: 'Germania One', cursive;}";

            head.AppendChild(metaCharSet);
            head.AppendChild(metaViewPort);
            head.AppendChild(linkElement1);
            head.AppendChild(linkElement2);
            head.AppendChild(style);

            var header1 = (HTMLHeadingElement)_document.CreateElement("h1");
            header1.TextContent = "Heading 1";
            var header2 = (HTMLHeadingElement)_document.CreateElement("h2");
            header2.TextContent = "Heading 2";

            _document.DocumentElement.LastElementChild.AppendChild(header1);
            _document.DocumentElement.LastElementChild.AppendChild(header2);

            var colors = new[] { "red", "orange", "black", "green", "blue", "indigo", "violet" };
            var alignment = new[] { "left", "right", "center" };
            for (var i = 0; i < 2; i++)
            {
                var paragraph = (HTMLParagraphElement)_document.CreateElement("p");
                paragraph.Id = $"par{i}";
                //paragraph.Style.SetProperty("font-weight", i % 2 == 0 ? "700" : "400", "");
                paragraph.Style.SetProperty("color", colors[i % 7], "");
                //paragraph.Style.SetProperty("text-align", alignment[i % 3], "");
                paragraph.TextContent = LoremNET.Lorem.Paragraph(50, 25);
                _document.DocumentElement.LastElementChild.AppendChild(paragraph);
            }

            HTMLImageElement img = (HTMLImageElement)_document.CreateElement("img");
            img.Src = "http://lorempixel.com/400/200/sports/1";
            img.Alt = "Placeholder 400x200";
            img.Title = "Placeholder image";
            _document.DocumentElement.LastElementChild.AppendChild(img);
            //Adding an ordered list
            HTMLOListElement orderedListElement = (HTMLOListElement)_document.CreateElement("ol");
            for (var i = 0; i < 10; i++)
            {
                HTMLLIElement listItem = (HTMLLIElement)_document.CreateElement("li");
                listItem.TextContent = $"Item {i + 1}";
                orderedListElement.AppendChild(listItem);
            }
            _document.DocumentElement.LastElementChild.AppendChild(orderedListElement);

            // Adding simple table 4x3
            var table = (HTMLTableElement)_document.CreateElement("table");
            var tBody = (HTMLTableSectionElement)_document.CreateElement("tbody");
            for (var i = 0; i < 4; i++)
            {
                var row = (HTMLTableRowElement)_document.CreateElement("tr");
                row.Id = "trow_" + i;
                for (var j = 0; j < 3; j++)
                {
                    var cell = (HTMLTableCellElement)_document.CreateElement("td");
                    cell.Id = $"cell{i}_{j}";
                    cell.TextContent = "Cell " + j;
                    row.AppendChild(cell);
                }
                tBody.AppendChild(row);
            }
            table.AppendChild(tBody);
            _document.DocumentElement.LastElementChild.AppendChild(table);

        }
    }

    internal class MyImageDevice : ImageDevice
    {
        public override bool BeginElement(Element element, System.Drawing.RectangleF rect)
        {
            Trace.WriteLine(element.TagName+" "+rect.ToString());
            return !element.TagName.Equals("H2") && base.BeginElement(element, rect);
        }

        public MyImageDevice(ImageRenderingOptions options, ICreateStreamProvider streamProvider) : base(options, streamProvider) { }

        public MyImageDevice(ImageRenderingOptions options, string file) : base(options, file) { }

        public MyImageDevice(ImageRenderingOptions options, Stream stream) : base(options, stream) { }
    }
}