本文将介绍如何使用Spire.Presentation for .NET给PowerPoint文档添加数字签名或删除PowerPoint文档中的现有数字签名。

添加数字签名

using Spire.Presentation;
using System;
using System.Security.Cryptography.X509Certificates;

namespace AddDigitalSignature
{
    class Program
    {
        static void Main(string[] args)
        {
            //创建Presentation实例
            Presentation ppt = new Presentation();
            //加载PowerPoint文档
            ppt.LoadFromFile("Input.pptx");

            //添加数字签名
            X509Certificate2 x509 = new X509Certificate2("gary.pfx", "e-iceblue");
            ppt.AddDigitalSignature(x509, "e-iceblue", DateTime.Now);

            //保存结果文档
            ppt.SaveToFile("AddDigitalSignature.pptx", FileFormat.Pptx2013);
        }
    }
}

Imports Spire.Presentation
Imports System
Imports System.Security.Cryptography.X509Certificates

Namespace AddDigitalSignature
    Class Program
        Private Shared Sub Main(ByVal args As String())
            Dim ppt As Presentation = New Presentation()
            ppt.LoadFromFile("Input.pptx")
            Dim x509 As X509Certificate2 = New X509Certificate2("gary.pfx", "e-iceblue")
            ppt.AddDigitalSignature(x509, "e-iceblue", DateTime.Now)
            ppt.SaveToFile("AddDigitalSignature.pptx", FileFormat.Pptx2013)
        End Sub
    End Class
End Namespace

结果文档：

删除数字签名

using Spire.Presentation;
using System;
using System.Security.Cryptography.X509Certificates;

namespace RemoveDigitalSignature
{
    class Program
    {
        static void Main(string[] args)
        {
            //创建Presentation实例
            Presentation ppt = new Presentation();
            //加载PowerPoint文档
            ppt.LoadFromFile("AddDigitalSignature.pptx");

            //判断文档中是否有数字签名
            if (ppt.IsDigitallySigned == true)
            {
                //删除所有数字签名
                ppt.RemoveAllDigitalSignatures();
            }

            //保存结果文档
            ppt.SaveToFile("RemoveDigitalSignature.pptx", FileFormat.Pptx2013);

        }
    }
}

Imports Spire.Presentation
Imports System
Imports System.Security.Cryptography.X509Certificates

Namespace RemoveDigitalSignature
    Class Program
        Private Shared Sub Main(ByVal args As String())
            Dim ppt As Presentation = New Presentation()
            ppt.LoadFromFile("AddDigitalSignature.pptx")

            If ppt.IsDigitallySigned = True Then
                ppt.RemoveAllDigitalSignatures()
            End If

            ppt.SaveToFile("RemoveDigitalSignature.pptx", FileFormat.Pptx2013)
        End Sub
    End Class
End Namespace

结果文档：