DocumentInfo

public class DocumentInfo : IDocumentInfo

using (Metadata metadata = new Metadata(Constants.InputXlsx))
{
    if (metadata.FileFormat != FileFormat.Unknown)
    {
        IDocumentInfo info = metadata.GetDocumentInfo();

        Console.WriteLine("File format: {0}", info.FileType.FileFormat);
        Console.WriteLine("File extension: {0}", info.FileType.Extension);
        Console.WriteLine("MIME Type: {0}", info.FileType.MimeType);
        Console.WriteLine("Number of pages: {0}", info.PageCount);
        Console.WriteLine("Document size: {0} bytes", info.Size);
        Console.WriteLine("Is document encrypted: {0}", info.IsEncrypted);
    }
}