Sort a worksheet by a column using Interop

Question

I've found various related code on the Internet but nothing seems to work. Maybe someone can point out my error:

// Get a Range of the data to sort
// (I also tried to use _worksheet.UsedRange, but it fails - why?)
var dataToSort = _worksheet.Range["A2", $"Z{lastLine}"];

// Sort range
dataToSort.Sort(_worksheet.Range["A2"]);

Funny enough it resorts the columns instead of the rows...

Actually I want to write something like this:

_worksheet.Sort(columnIndex: 1);

But I can't find a suitable overload.

My Sheet looks like this:

1 |      |       |
2 | Z    | Data2 |
3 | A    | Data1 |

I want it to look like this afterwards:

1 |      |       |
2 | A    | Data1 |
3 | Z    | Data2 |

(Using Excel 2019 and Excel Interop 15 for an xlsx file)

Answer 1

Ouch, for whatever reason the sort orientation default is xlSortRows . I had to switch to xlSortColumns and now it works with this simple oneliner:

_worksheet.UsedRange.Sort(_worksheet.Columns[1], Orientation: XlSortOrientation.xlSortColumns);