SignTime

IDigitalSignature.SignTime property

文件签署的时间。 只读DateTime。

public DateTime SignTime { get; }

例子

[C#]
using (Presentation pres = new Presentation("SomePresentationSigned.pptx"))
{
    foreach (DigitalSignature signature in pres.DigitalSignatures)
        Console.WriteLine("Signature check: " + (signature.IsValid ? "VALID" : "INVALID") + ", Signing time: " + signature.SignTime);
}

也可以看看

IsValid