NPOI.XSSF.UserModel.XSSFWorkbook.IsSheetHidden C# (CSharp) Method

        public bool IsSheetHidden(int sheetIx)
        {
            ValidateSheetIndex(sheetIx);
            CT_Sheet ctSheet = sheets[sheetIx].sheet;
            return ctSheet.state == ST_SheetState.hidden;
        }