C#实现给PDF文档设置过期时间

using Spire.Pdf;
using Spire.Pdf.Actions;

namespace SetExpiryDate
{
    class Program
    {
        static void Main(string[] args)
        {
            //创建PdfDocument类的对象，并加载PDF文档
            PdfDocument pdf = new PdfDocument();
            pdf.LoadFromFile("test.pdf");

            //通过JavaScript设置过期时间，过期警告信息并关闭文档
            string javaScript = "var rightNow = new Date();"
                    + "var endDate = new Date('June 20, 2021 23:59:59');"
                    + "if(rightNow.getTime() > endDate) {"
                    + "app.alert('该文档已过期。请联系管理人员获取最新文档！',1);"
                    + "this.closeDoc(); }";

            //根据JS创建PdfJavaScriptAction 
            PdfJavaScriptAction js = new PdfJavaScriptAction(javaScript);

            //将PdfJavaScriptAction设置为文档打开后的动作
            pdf.AfterOpenAction = js;

            //保存文档
            pdf.SaveToFile("SetExpiryDate.pdf", FileFormat.PDF);
        }
    }
}

Imports Spire.Pdf
Imports Spire.Pdf.Actions

Namespace SetExpiryDate
    Class Program
        Private Shared Sub Main(args As String())
            '创建PdfDocument类的对象，并加载PDF文档
            Dim pdf As New PdfDocument()
            pdf.LoadFromFile("test.pdf")

            '通过JavaScript设置过期时间，过期警告信息并关闭文档
            Dim javaScript As String = "var rightNow = new Date();" + "var endDate = new Date('June 20, 2021 23:59:59');" + "if(rightNow.getTime() > endDate) {" + "app.alert('该文档已过期。请联系管理人员获取最新文档！',1);" + "this.closeDoc(); }"

            '根据JS创建PdfJavaScriptAction 
            Dim js As New PdfJavaScriptAction(javaScript)

            '将PdfJavaScriptAction设置为文档打开后的动作
            pdf.AfterOpenAction = js

            '保存文档
            pdf.SaveToFile("SetExpiryDate.pdf", FileFormat.PDF)
        End Sub
    End Class
End Namespace