实现的代码如下：
protected void Page_Load(object sender, EventArgs e)
{
if (IsPostBack)
{
return;
}
FpSpread1.Sheets[0].ReferenceStyle = FarPoint.Web.Spread.Model.ReferenceStyle.R1C1;
this.FpSpread1.ClientAutoCalculation = true;
this.FpSpread1.Sheets[0].Cells[0, 2].Tag = "单价";
this.FpSpread1.Sheets[0].Cells[1, 3].Tag = "数量";
this.FpSpread1.Sheets[0].Cells[2, 3].Tag = "总金额";
FarPoint.Web.Spread.Cell _unitPrice = this.FpSpread1.Sheets[0].GetCellFromTag(this.FpSpread1.Sheets[0].Cells[0, 0], "单价");
FarPoint.Web.Spread.Cell _quantity = this.FpSpread1.Sheets[0].GetCellFromTag(this.FpSpread1.Sheets[0].Cells[0, 0], "数量");
FarPoint.Web.Spread.Cell _toalPrice = this.FpSpread1.Sheets[0].GetCellFromTag(this.FpSpread1.Sheets[0].Cells[0, 0], "总金额");
this.FpSpread1.Sheets[0].AllowUserFormulas = true;
string formula = "PRODUCT(" + "R" + (_unitPrice.Row.Index + 1).ToString() + "C" + (_unitPrice.Column.Index + 1).ToString() + "," + "R" + (_quantity.Row.Index + 1).ToString() + "C" + (_quantity.Column.Index + 1).ToString() + ")";
_toalPrice.Formula = formula;
}
