SignatureAppearance.cs
// 完毕:
using System;
using System.IO;
using System.Drawing;
using GrapeCity.Documents.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
{
// 此示例演示了如何使用 .pfx 文件创建 PDF 并对其进行签名,
// 指定自定义 AppearanceStream 来表示签名。
// 这个示例与SignDoc类似,只不过它添加了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("你好世界!" +
"",
tf, new PointF(72, 72));
// 初始化测试证书:
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(),
};
// 创建一个签名字段来保存签名:
var sf = new SignatureField();
// 将签名字段添加到文档中:
doc.AcroForm.Fields.Add(sf);
// 连接签名字段和签名属性:
sp.SignatureField = sf;
// 设置签名字段:
sf.Widget.Rect = new RectangleF(page.Size.Width - 72 * 4, 72 * 2, 72 * 3, 72);
sf.Widget.Page = page;
// 小部件视觉道具将被下面设置的 sf.Widget.AppearanceStreams.Normal.Default 覆盖:
sf.Widget.BackColor = Color.PeachPuff;
sf.Widget.Border = new GrapeCity.Documents.Pdf.Annotations.Border()
{
Color = Color.SaddleBrown,
Width = 3,
};
sf.Widget.ButtonAppearance.Caption = $"Signer: {sp.SignerName}\r\nLocation: {sp.Location}";
// 创建自定义签名外观流:
var rc = new RectangleF(PointF.Empty, sf.Widget.Rect.Size);
var fxo = new FormXObject(doc, rc);
rc.Inflate(-4, -4);
fxo.Graphics.FillEllipse(rc, Color.CornflowerBlue);
fxo.Graphics.DrawEllipse(rc, new GCDRAW.Pen(Color.RoyalBlue, 3));
rc.Inflate(-5, -5);
fxo.Graphics.DrawEllipse(rc, new GCDRAW.Pen(Color.LightSteelBlue, 1));
fxo.Graphics.DrawString($"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;
// 重置签名外观以便使用小部件外观流:
sp.SignatureAppearance = null;
// 签署并保存文档:
// 笔记:
// - 签名和保存是一个原子操作,两者不能分开。
// - 传递给 Sign() 方法的流必须可读。
doc.Sign(sp, stream);
// 完成(生成并签名的文档已保存到“流”)。
return doc.Pages.Count;
}
}
}