EPPlus autofilter only working on last cell

Question

I would like each cell in the header to contain an autofilter. Below is the code I'm trying to use however the autofilter only gets set on the last cell specified.

For example, if I comment out the autofilter command for K1, the spreadsheet will be created with C1 being the only cell with an autofilter.

        //Headers         ws.Cells["A1"].Value = "ChannelCode";         ws.Cells["A1"].AutoFilter = true;         ws.Cells["B1"].Value = "DrmTerrDesc";         ws.Cells["B1"].AutoFilter = true;         ws.Cells["C1"].Value = "IndDistrnId";         ws.Cells["C1"].AutoFilter = true;         ws.Cells["D1"].Value = "StateCode";         ws.Cells["D1"].AutoFilter = true;         ws.Cells["E1"].Value = "ZipCode";         ws.Cells["E1"].AutoFilter = true;         ws.Cells["F1"].Value = "EndDate";         ws.Cells["F1"].AutoFilter = true;         ws.Cells["G1"].Value = "EffectiveDate";         ws.Cells["G1"].AutoFilter = true;         ws.Cells["H1"].Value = "LastUpdateId";         ws.Cells["H1"].AutoFilter = true;         ws.Cells["I1"].Value = "ErrorCodes";         ws.Cells["I1"].AutoFilter = true;         ws.Cells["J1"].Value = "Status";         ws.Cells["J1"].AutoFilter = true;         ws.Cells["K1"].Value = "Id";         ws.Cells["K1"].AutoFilter = true; 

Answer 1

EPPlus .AutoFilter is a little buggy... I suggest doing it using a range like this:

ws.Cells["A1:K1"].AutoFilter = true; 

Answer 2

For all sheet data range

worksheet.Cells[worksheet.Dimension.Address].AutoFilter=true;