This article demonstrates how to detect whether a PDF file is encrypted or not by using Spire.PDF for .NET. Spire.PDF offers a method named IsPasswordProtected(string fileName) which returns a boolean value. If the value is true, means the PDF is encrypted with password, otherwise it's not.
C#
using Spire.Pdf;
using System;
namespace PdfDemo
{
class Program
{
static void Main(string[] args)
{
string fileName = "Sample.pdf";
bool value = PdfDocument.IsPasswordProtected(fileName);
Console.WriteLine(value);
Console.ReadKey();
}
}
}
VB.NET
Imports Spire.Pdf
Imports System
Namespace PdfDemo
Class Program
Private Shared Sub Main(ByVal args() As String)
Dim fileName As String = "Sample.pdf"
Dim value As Boolean = PdfDocument.IsPasswordProtected(fileName)
Console.WriteLine(value)
Console.ReadKey
End Sub
End Class
End Namespace
After running the project, we get the Output that shows the PDF file is password protected:
