GridView中如何取得隐藏列的值？

直接对 <asp:BoundField  隐藏列取值不行，改用模板列实现

<asp:TemplateField Visible="false">
                    <ItemTemplate>
                        <asp:label ID="lblTask" runat="server" Text='<%# Eval("task_status") %>' />
                    </ItemTemplate>
            </asp:TemplateField>

然后，

protected void SmartGrid_RowDataBound(object sender, GridViewRowEventArgs e)
    {
        if (e.Row.RowType == DataControlRowType.DataRow)
        {
            switch (((Label)e.Row.FindControl("lblTask")).Text)
            {
                case "0":
                    e.Row.CssClass = "color_task_init";
                    break;
                case "1":
                    e.Row.CssClass = "color_task_back";
                    break;
                case "2":
                    e.Row.CssClass = "color_task_wait";
                    break;
                case "3":
                    e.Row.CssClass = "color_task_confirm";
                    break;
                case "4":
                    e.Row.CssClass = "color_task_finish";
                    break;
                case "10":
                    e.Row.CssClass = "color_task_cancel";
                    break;
                case "&nbsp;":
                    e.Row.CssClass = "color_terminal";
                    break;
                default:
                    e.Row.CssClass = "color_terminal";
                    break;
            }
        }
    }