//// 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 GrapeCity.Documents.Pdf;
namespace DsPdfWeb.Demos{    // This sample loads the PDF file created by the HelloWorld sample,    // adds a short text note to the first page, and saves the result.    public class LoadPDF    {        public int CreatePDF(Stream stream)        {            // IMPORTANT: when working with an existing PDF file using GcPdfDocument.Load() method,            // the stream passed to that method MUST REMAIN OPEN while working with the document.            // This is because Load() does not load the whole PDF document into memory right away,            // instead it loads the various parts of the PDF as needed.            // The stream is only used for reading, and the original file itself is not modified.            // To save the changes you need to call one of the GcPdfDocument.Save() overloads            // as usual.            using var fs = File.OpenRead(Path.Combine("Resources", "PDFs", "HelloWorld.pdf"));            var doc = new GcPdfDocument();            doc.Load(fs);            // Add note to the (only) page in the doc:            var page = doc.Pages.Last;            Common.Util.AddNote(                "This text was added to the original \"Hello World\" PDF.",                page,                new RectangleF(72, 72 * 3, page.Size.Width - 72 * 2, 72));            // Done:            doc.Save(stream);            return doc.Pages.Count;        }    }}