excel How to make the "+"symbol at the left side of the outline

Question

I am using range.group method from the Microsoft.Office.Interop.Excel.dll and it works to group up the columns or rows as the outline level in the Excel document; but there comes the question of how to set the "+"symbol at the left side, but not it's default position at the right side according to the last columns or rows.

What method is used for controlling the direction and how to use this method. It would be best if that's an example,.

Answer 1

In excel: Data/Group and Outline/Settings...

In code:

range.Group(oMissing, oMissing, oMissing, oMissing);

//for rows
worksheet.Outline.SummaryRow = Excel.XlSummaryRow.xlSummaryAbove;

//for columns
worksheet.Outline.SummaryColumn = Excel.XlSummaryColumn.xlSummaryOnLeft;

Answer 2

To apply it on the left without using VBA:

In Excel: Data-> Outline. Click on the arrow on the bottom right corner of the ribbon (The arrow is pointing down right.)

It will open the Outline Settings.

Untick "Summary column on the right on the right of detail." Click Apply Styles.