//// This code is part of Document Solutions for PDF .NET demos.// Copyright (c) MESCIUS inc. All rights reserved.//using System.IO;using System.Drawing;using System.Linq;using GrapeCity.Documents.Common;using GrapeCity.Documents.Pdf;
namespace DsPdfWeb.Demos{    // This sample loads the PDF file created by the Transforms sample,    // finds all occurrences of a string in the loaded document,    // and highlights these occurrences. Two points of interest about this sample:    // - The texts in the original document are graphically transformed,    //   but the quadrilaterals supplied by the FindText method allows you to easily    //   highlight the finds even in that case.    // - The sample inserts a new content stream at index 0 of the page,    //   this ensures that the highlighting is drawn UNDER the original content.    //   (The same approach may be used to add watermarks etc. to existing files.)    public class FindTransformed    {        public int CreatePDF(Stream stream)        {            // The original file stream must be kept open while working with the loaded PDF,            // see @{LoadPDF} for details:            using var fs = File.OpenRead(Path.Combine("Resources", "PDFs", "Transforms.pdf"));            var doc = new GcPdfDocument();            doc.Load(fs);            // Find all 'Text drawn at', using case-sensitive search:            var finds = doc.FindText(                new FindTextParams("Text drawn at", false, true),                OutputRange.All);
            // Highlight all finds: first, find all pages where the text was found            var pgIndices = finds.Select(f_ => f_.PageIndex).Distinct();            // Loop through pages, on each page insert a new content stream at index 0,            // so that our highlights go UNDER the original content:            foreach (int pgIdx in pgIndices)            {                var page = doc.Pages[pgIdx];                PageContentStream pcs = page.ContentStreams.Insert(0);                var g = pcs.GetGraphics(page);                foreach (var find in finds.Where(f_ => f_.PageIndex == pgIdx))                {                    foreach (var ql in find.Bounds)                    {                        // Note the solid color used to fill the polygon:                        g.FillPolygon(ql, Color.CadetBlue);                        g.DrawPolygon(ql, Color.Blue);                    }                }            }            // Done:            doc.Save(stream);            return doc.Pages.Count;        }    }}