For unit testing one of my components, I have an XLSX and an XLS file that have two sheets filled with the formula:
=CONCATENATE("Sheet #: ",SHEET(A1),", Row: ",ROW(A1),", Column: ",COLUMN(A1))
When I load it in XlsIo and export to a DataTable, the "Sheet #" gives wildly inaccurate results, like "Sheet #: 6" or "Sheet #: 8" when the maximum possible is 2. I've tested directly accessing the CalculatedValue after calling EnableSheetCalculations() and get the same bad values.
Note that this doesn't always fail. The first time the engine is used, sometimes the first-run test passes while all the others fail.
I've attached an NUnit testing project that tests the engine with XLSX, XLS, and CSV files. Running the tests will show the failures.
ClassLibrary1_e8ddd0b.zip
