Commented Unassigned: Can't capture empty sheet [11864]

I hava an excel file, and in Sheet1 there some data, Sheet2 and Sheet3 by default they are empty. I read data by ExcelReaderFactory.CreateOpenXmlReader(stream).AsDataSet(), Sheet1's data is correct, but Only one DataTable int the returned dataset, I even can't get Sheet2 and Sheet3's name.
How can I do it correctly?

Thank you all.
Comments: ** Comment from web user: rwilson513 **

One good example of wanting to read an empty sheet is for unit tests, e.g. to mock an empty DataTable being returned from a query.