'''' This code is part of Document Solutions for PDF .NET demos.'' Copyright (c) MESCIUS inc. All rights reserved.''Imports System.IOImports System.DrawingImports GrapeCity.Documents.PdfImports GrapeCity.Documents.Pdf.AcroFormsImports GrapeCity.Documents.Pdf.GraphicsImports GrapeCity.Documents.TextImports System.Security.Cryptography.X509CertificatesImports GCDRAW = GrapeCity.Documents.Drawing
'' 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    Function CreatePDF(ByVal stream As Stream) As Integer        Dim doc = New GcPdfDocument()        Dim page = doc.NewPage()        Dim tf = New TextFormat() With {.Font = StandardFonts.Times, .FontSize = 14}        page.Graphics.DrawString(            "Hello, World!" + vbLf +            "Signed by DsPdfWeb SignatureAppearance sample.",            tf, New PointF(72, 72))
        '' Init a test certificate:        Dim pfxPath = Path.Combine("Resources", "Misc", "DsPdfTest.pfx")        Dim cert = New X509Certificate2(File.ReadAllBytes(pfxPath), "qq",            X509KeyStorageFlags.MachineKeySet Or X509KeyStorageFlags.PersistKeySet Or X509KeyStorageFlags.Exportable)        Dim sp = New SignatureProperties() With {            .SignatureBuilder = New Pkcs7SignatureBuilder() With {                .CertificateChain = New X509Certificate2() {cert}            },            .Location = "DsPdfWeb Demo Browser",            .SignerName = "DsPdfWeb",            .SigningDateTime = Util.TimeNow()        }
        '' Create a signature field to hold the signature:        Dim 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() With            {                .Color = Color.SaddleBrown,                .Width = 3            }        sf.Widget.ButtonAppearance.Caption = $"Signer: {sp.SignerName}{vbLf}Location: {sp.Location}"        '' Create custom signature appearance stream:        Dim rc = New RectangleF(PointF.Empty, sf.Widget.Rect.Size)        Dim fxo = New FormXObject(doc, rc)        rc.Inflate(-4, -4)        fxo.Graphics.FillEllipse(rc, Color.CornflowerBlue)        fxo.Graphics.DrawEllipse(rc, New GCDRAW.Pen(Color.RoyalBlue, 3))        rc.Inflate(-5, -5)        fxo.Graphics.DrawEllipse(rc, New GCDRAW.Pen(Color.LightSteelBlue, 1))        fxo.Graphics.DrawString($"Signed by {sp.SignerName}{vbLf}on {Util.TimeNow():yyyy-MM-dd}.",            New TextFormat() With            {                .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 = Nothing
        '' 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    End FunctionEnd Class