Returns the week number in the year.
| Name | Type | Description |
| arg1 | any | Is the date-time code used by Microsoft Excel for date and time calculation. |
| arg2 | any | Is a number (1 or 2) that determines the type of the return value. |
builder.CreateFile("xlsx");
const oWorksheet = Api.GetActiveSheet();
var oFunction = Api.GetWorksheetFunction();
var ans = oFunction.WEEKNUM("11/5/2018", 2);
oWorksheet.GetRange("C1").SetValue(ans);
builder.SaveFile("xlsx", "WEEKNUM.xlsx");
builder.CloseFile();