When giving the end-user the ability to open a PDF file, sometimes you can’t predict whether or not the file will be password protected or not. The following sample method demonstrates how to perform this check and open the document accordingly:

Private Sub _btnOpen_Click(sender As Object, e As RoutedEventArgs)

        Dim dlg = New OpenFileDialog()

        dlg.Filter = "Pdf files (*.pdf)|*.pdf"

        If dlg.ShowDialog().Value Then

            Dim ms = New System.IO.MemoryStream()

            Using stream = dlg.File.OpenRead()
               
              stream.CopyTo(ms)

            End Using

            LoadProtectedDocument(ms, Nothing)
       
            End If

    End Sub

void _btnOpen_Click(object sender, RoutedEventArgs e)

        {
            var dlg = new OpenFileDialog();

            dlg.Filter = "Pdf files (*.pdf)|*.pdf";

            if (dlg.ShowDialog().Value)

            {
                var ms = new System.IO.MemoryStream();

                using (var stream = dlg.File.OpenRead())
                {

                    stream.CopyTo(ms);
                }

                LoadProtectedDocument(ms, null);

            }
        }

When giving the end-user the ability to open a PDF file, sometimes you can’t predict whether or not the file will be password protected or not. The following sample method demonstrates how to perform this check and open the document accordingly: