View metadata of a document | https://docs.conholdate.com/net/view-metadata

view-metadata.cs

// Constants.InputXlsx is an absolute or relative path to your document. Ex: @"C:\Docs\source.xlsx"
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);
	}
}

Read the complete article: https://docs.conholdate.com/net/view-metadata