//// 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;using GrapeCity.Documents.Pdf.Security;
namespace DsPdfWeb.Demos{    // This sample shows how to set restrictions on a PDF,    // e.g. restricting the ability to print or copy content    // from the document.    // See also the SecurityHandlers sample, which shows    // how to examine restrictions in a loaded PDF.    public class DocumentRestrictions    {        public int CreatePDF(Stream stream)        {            // Create a new PDF document:            var doc = new GcPdfDocument();            var rc = Common.Util.AddNote("This document has the following restrictions:\n" +                "  - printing is not allowed;\n" +                "  - content copying is not allowed;\n" +                "  - document assembly is not allowed.", doc.NewPage());
            // Create a Rev4 security handler and specify some restrictions:            var ssh4 = new StandardSecurityHandlerRev4()            {                // EncryptionAlgorithm = EncryptionAlgorithm.AES,                // EncryptStrings = true,                PrintingPermissions = PrintingPermissions.Disabled,                CopyContent = false,                EditingPermissions = EditingPermissions.Disabled            };            // Assign the handler we created to the document so that it is used when saving the PDF:            doc.Security.EncryptHandler = ssh4;
            // Add a text prompting the user to check out the source code:            var pg = doc.Pages.Last;            var g = pg.Graphics;            var tl = g.CreateTextLayout();            tl.AppendLine("See the source code of this demo for details on how to use a security handler to set PDF document restrictions.");            tl.MaxWidth = pg.Bounds.Width - rc.X * 2;            tl.MarginLeft = rc.X;            tl.MarginTop = rc.Bottom + 36;            g.DrawTextLayout(tl, PointF.Empty);
            // Done:            doc.Save(stream);            return doc.Pages.Count;        }    }}