Workbook workbook = new Workbook();
workbook.LoadFromFile(@"input.xlsx");
Worksheet sheet = workbook.Worksheets[0];
sheet.Range["A1"].HtmlString = "<div>xxxx<br>yyyy</div>";

Workbook workbook = new Workbook();
workbook.LoadFromFile(@"input.xlsx");
Worksheet worksheet = workbook.Worksheets[0];
PivotTable table = worksheet.PivotTables[0] as PivotTable;
PivotConditionalFormatCollection pcfs = table.PivotConditionalFormats;
PivotConditionalFormat pc = pcfs.AddPivotConditionalFormat();
IConditionalFormat cf = pc.AddCondition();
cf.FormatType = ConditionalFormatType.ContainsBlanks;
cf.FillPattern = ExcelPatternType.Solid;
cf.BackColor = Color.Red;

bool havepwd = Workbook.IsPasswordProtected(File.OpenRead(inputFile));
var docBytes = File.ReadAllBytes(inputFile);
MemoryStream ms = new MemoryStream(docBytes);
bool havepwd = Workbook.IsPasswordProtected(ms);

Workbook book = new Workbook();
book.LoadFromFile("input.xlsx");
Worksheet sheet = book.Worksheets["sheet1"];
PrstGeomShapeCollection prstGeomShapeCollection = sheet.PrstGeomShapes;
IPrstGeomShape shape = prstGeomShapeCollection["a"];
shape.LinkedCell.RangeAddressLocal;

Workbook workbook = new Workbook();
workbook.LoadFromFile("input.xlsx");
workbook.Worksheets[0].CalculateAllValue();
workbook.Worksheets[0].Range["A1：C3"].CalculateAllValue();