//// 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.AcroForms;using GrapeCity.Documents.Pdf.Graphics;using GrapeCity.Documents.Text;using System.Security.Cryptography.X509Certificates;using GCTEXT = GrapeCity.Documents.Text;using GCDRAW = GrapeCity.Documents.Drawing;
namespace DsPdfWeb.Demos{    // This sample demonstrates how to create and sign a PDF with a .pfx file,    // specifying a custom AppearanceStream to represent the signature.    // This sample is similar to SignDoc, except that it adds the AppearanceStream.    public class SignatureAppearance    {        public int CreatePDF(Stream stream)        {            var doc = new GcPdfDocument();            var page = doc.NewPage();            var tf = new TextFormat() { Font = StandardFonts.Times, FontSize = 14 };            page.Graphics.DrawString("Hello, World!\n" +                "Signed by DsPdfWeb SignatureAppearance sample.",                tf, new PointF(72, 72));
            // Init a test certificate:            var pfxPath = Path.Combine("Resources", "Misc", "DsPdfTest.pfx");            var cert = new X509Certificate2(File.ReadAllBytes(pfxPath), "qq",                X509KeyStorageFlags.MachineKeySet | X509KeyStorageFlags.PersistKeySet | X509KeyStorageFlags.Exportable);            var sp = new SignatureProperties()            {                SignatureBuilder = new Pkcs7SignatureBuilder()                {                    CertificateChain = new X509Certificate2[] { cert }                },                Location = "DsPdfWeb Demo Browser",                SignerName = "DsPdfWeb",                SigningDateTime = Common.Util.TimeNow(),            };
            // Create a signature field to hold the signature:            var sf = new SignatureField();            // Add the signature field to the document:            doc.AcroForm.Fields.Add(sf);            // Connect the signature field and signature props:            sp.SignatureField = sf;
            // Set up the signature field:            sf.Widget.Rect = new RectangleF(page.Size.Width - 72 * 4, 72 * 2, 72 * 3, 72);            sf.Widget.Page = page;            // Widget visual props will be overridden by sf.Widget.AppearanceStreams.Normal.Default set below:            sf.Widget.BackColor = Color.PeachPuff;            sf.Widget.Border = new GrapeCity.Documents.Pdf.Annotations.Border()            {                Color = Color.SaddleBrown,                Width = 3,            };            sf.Widget.ButtonAppearance.Caption = $"Signer: {sp.SignerName}\r\nLocation: {sp.Location}";            // Create custom signature appearance stream:            var rc = new RectangleF(PointF.Empty, sf.Widget.Rect.Size);            var fxo = new FormXObject(doc, rc);            rc.Inflate(-4, -4);            fxo.Graphics.FillEllipse(rc, Color.CornflowerBlue);            fxo.Graphics.DrawEllipse(rc, new GCDRAW.Pen(Color.RoyalBlue, 3));            rc.Inflate(-5, -5);            fxo.Graphics.DrawEllipse(rc, new GCDRAW.Pen(Color.LightSteelBlue, 1));            fxo.Graphics.DrawString($"Signed by {sp.SignerName}\non {Common.Util.TimeNow():yyyy-MM-dd}.",                new TextFormat()                {                    FontName = "Times New Roman",                    FontSize = 14,                    FontItalic = true,                    ForeColor = Color.Navy                },                fxo.Bounds,                TextAlignment.Center, ParagraphAlignment.Center, false);            sf.Widget.AppearanceStreams.Normal.Default = fxo;
            // Reset signature appearance so that the widget appearance stream is used:            sp.SignatureAppearance = null;
            // Sign and save the document:            // NOTES:            // - Signing and saving is an atomic operation, the two cannot be separated.            // - The stream passed to the Sign() method must be readable.            doc.Sign(sp, stream);
            // Done (the generated and signed docment has already been saved to 'stream').            return doc.Pages.Count;        }    }}