国产PDF管理控件Spire.PDF使用教程：使用C#在 PDF 中添加不可见数字签名

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C#

using Spire.Pdf;using Spire.Pdf.Interactive.DigitalSignatures;using System.Security.Cryptography.X509Certificates;namespace InvisibleDigitalSignature{    class Program    {        static void Main(string[] args)        {            //初始化一个PdfDocument实例            PdfDocument pdf = new PdfDocument();            //加载PDF文档            pdf.LoadFromFile("sample.pdf");            //添加签名            X509Certificate2 x509 = new X509Certificate2(@"cer.pfx", "e-iceblue");            PdfOrdinarySignatureMaker signatureMaker = new PdfOrdinarySignatureMaker(pdf, x509);            signatureMaker.MakeSignature("signName");            signatureMaker.SetLocation("Chengdu");            signatureMaker.SetReason("Edit limited");               //保存文档            pdf.SaveToFile("result.pdf", FileFormat.PDF);            System.Diagnostics.Process.Start("result.pdf");        }    }}

VB.NET

Imports Spire.PdfImports Spire.Pdf.Interactive.DigitalSignaturesImports System.Security.Cryptography.X509CertificatesNamespace InvisibleDigitalSignatureClass ProgramPrivate Shared Sub Main(args As String())'初始化一个PdfDocument实例Dim pdf As New PdfDocument()'加载PDF文档pdf.LoadFromFile("sample.pdf")'添加签名Dim x509 As New X509Certificate2("cer.pfx", "e-iceblue")Dim signatureMaker As New PdfOrdinarySignatureMaker(pdf, x509)signatureMaker.MakeSignature("signName")signatureMaker.SetLocation("Chengdu")signatureMaker.SetReason("Edit limited")'保存文档pdf.SaveToFile("result.pdf", FileFormat.PDF)System.Diagnostics.Process.Start("result.pdf")End SubEnd ClassEnd Namespace 

数字签名效果：