I am using Aspose.Cells 184.108.40.206 with the following code:
worksheet.Cells.Columns[colIdx].Style.Custom = "dd/mm/yyyy";
The contents of the column remain in the default format.
I have also tried creating a style and applying it, like this:
Style style = worksheet.Workbook.Styles[worksheet.Workbook.Styles.Add()];
style.Custom = "dd/mm/yyyy";
StyleFlag flag = new StyleFlag();
worksheet.Cells.ApplyColumnStyle(colIdx, style, flag);
That doesn't work either, nor does worksheet.Cells.Columns[colIdx].ApplyStyle(...).
Thanks for your help.