Adds all the numbers in a range of cells.
This method doesn't have any parameters.
builder.CreateFile("xlsx"); var oWorksheet = Api.GetActiveSheet(); var oFunction = Api.GetWorksheetFunction(); oWorksheet.GetRange("A1").SetValue(oFunction.SUM(145, 37, 236, 69, 567, 92)); builder.SaveFile("xlsx", "SUM.xlsx"); builder.CloseFile();