DX插件AspxGridview根据单元格值得不同设置字体颜色

/// <summary>
    /// 销售对账单余额为负时红色字体显示
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected void grid_HtmlRowCreated(object sender, ASPxGridViewTableRowEventArgs e)
    {
        if (e.RowType != DevExpress.Web.ASPxGridView.GridViewRowType.Data) return;
        string str = e.GetValue("BalanceAmount").ToString();
        if (str.Contains("-"))
        {
            e.Row.Cells[13].Style.Add("Color", "Red");
        }  
    }