无法从嵌套 gridview 内的输入中获取新值

如何解决无法从嵌套 gridview 内的输入中获取新值

我有一个看起来像这样的 aspx：

<asp:Panel ID="pnlPesquisa" runat="server" Visible="false" CssClass="content">
<asp:DataGrid ID="dtgPacotes" runat="server" AutoGenerateColumns="False" CssClass="cssTable"
        PagerStyle-HorizontalAlign="Center" PagerStyle-Mode="NumericPages" PageSize="20"
        ShowFooter="False" AllowPaging="True" DataKeyField="ID_PACOTE">
        <HeaderStyle CssClass="cssDtgHeader" HorizontalAlign="Center" />
        <Columns>
            <asp:TemplateColumn>
                <ItemTemplate>
                    <i class="fa fa-plus" runat="server" id="plusMinus"></i>
                    <asp:Panel ID="pnlOrders" runat="server" Style="display: none">
                        <asp:UpdatePanel runat="server" ID="updBiometria" UpdateMode="Conditional">
                        <ContentTemplate>
                        <asp:DataGrid ID="dtgPropostas" AlternatingItemStyle-Wrap="true" OnItemDataBound="dtgPropostas_ItemDataBound" OnItemCommand="dtgPropostas_ItemCommand" runat="server" AutoGenerateColumns="false" CssClass="cssTable dtgPropostas" DataKeyNames="ID_FIN_SOL">
                            <Columns>
                                <!-- Randon columns-->
                                <asp:TemplateColumn HeaderText="CONTROLE BIOMETRIA" ItemStyle-CssClass="c-biometria">
                                    <ItemTemplate>                                                        
                                        <asp:Label ID="lblBiometria" runat="server" />
                                        <asp:DropDownList runat="server" ID="ddlBiometria" OnSelectedIndexChanged="ddlBiometria_SelectedIndexChanged">

                                        </asp:DropDownList>

                                        <asp:ImageButton ID="btnCancelarEdit" runat="server" AlternateText="CANCELAR" Visible="false" ToolTip="CANCELAR" CausesValidation="False" CommandName="btnCancelarEdit" Width="16" ImageUrl="~/pict/ico_sml/critical.svg" OnClientClick="" />                            
                                    </ItemTemplate>
                            </Columns>
                        </asp:DataGrid>
                        </ContentTemplate>
                        </asp:UpdatePanel>
                    </asp:Panel>
                </ItemTemplate>
            </asp:TemplateColumn>
            <!-- Randon columns-->
        </Columns>
        <PagerStyle HorizontalAlign="Center" Mode="NumericPages" CssClass="paginator-tr" />
</asp:DataGrid>
</asp:Panel>

我正在为 de If Not IsPostBack 块中的外部数据网格进行数据绑定，为 dtgPacotes_ItemDataBound 块中的内部数据网格进行数据绑定，并且我正在为 de dtgPropostas_ItemDataBound 中的 ddlBiometria 绑定选项。

问题是 dtgPropostas_ItemCommand，ddlBiometria 下拉列表的值始终是第一个选项，无论我选择什么。

    Protected Sub dtgPropostas_ItemCommand(ByVal source As Object,ByVal e As System.Web.UI.WebControls.DataGridCommandEventArgs)
    'Stuff    
    Case "btnCancelarEdit"
        Dim row As DataGridItem = DirectCast(DirectCast(e.CommandSource,Control).NamingContainer,DataGridItem)
        Dim ddlBiometria As DropDownList = row.FindControl("ddlBiometria")
        Dim xb = ddlBiometria.SelectedValue
    'Other stuff
End Sub