How to clear Excel cell contents but keep formulas in C#?

Question

.NET

I am making a converter and I need to fill in a large table with a bunch of formulas.
Accordingly, headings and formulas should be left, and the rest of the content should be deleted.
Tried this method:

this._sheetDestination.Range["A4", "A" + firstCellDestination.Row].EntireRow.Delete(XlDirection.xlUp);

and

this._sheetDestination.Range["A4", "A" + firstCellDestination.Row].EntireRow.Clear();

But in both cases the formulas disappear.

Answer 1

And if you loop through each cell from Range["A4", "A" + firstCellDestination.Row] and do not delete those that start with the "=" sign.