I am using this syntax to dump worksheet contents into a datatable:
sheet.ExportDataTable(sheet.UsedRange, ExcelExportDataTableOptions.ColumnNames | ExcelExportDataTableOptions.DetectColumnTypes)
It seems that the detection of column types is looking only at the first row, i.e. the row containing column names, and as they are all non-numeric, it never figures out that the subsequent rows actually contain numeric or date information.
Isn't this a bug? [using version 10.204.0.75]