FpSpread1.Sheets[0].AlternatingRows.Count = 3;
FpSpread1.Sheets[0].AlternatingRows.Item[0].BackColor = Color.Red;
FpSpread1.Sheets[0].AlternatingRows.Item[1].BackColor = Color.Blue;
FpSpread1.Sheets[0].AlternatingRows.Item[2].BackColor = Color.Green;
FpSpread1.Sheets(0).AlternatingRows.Count = 3
FpSpread1.Sheets(0).AlternatingRows.Parent(0).BackColor = Color.Red
FpSpread1.Sheets(0).AlternatingRows.Parent(1).BackColor = Color.Blue
FpSpread1.Sheets(0).AlternatingRows.Parent(2).BackColor = Color.Green