C# 无法在服务器端访问html表。asp.net

我在表单视图中有一个html表。我让它在runat=“server”上运行，但在服务器端，id-tblDemandData无法访问它。我的代码是-

<asp:FormView ID="DemandDataView" runat="server">
    <ItemTemplate>
        <div id="DemandDataDIV" runat="server" visible="true">
            <asp:Button Text="exportBtn" runat="server" ID="btnExport" OnClick="btnExport_Click" />
            <hr />
            <div class="headingtext" runat="server" id="tblDiv" style="width: 100%; margin-bottom: 10px;"><%= LocalString("DemandDataText")%></div>
            <table border="0" runat="server" id="tblDemandData" cellpadding="3" cellspacing="0" class="tabletext">
                <tr>
                    <td class="tabletextbold" style="width: 240px;text-align:right"></td>
                    <td class="tabletextbold" style="width: 151px;text-align:right"><%= LocalString("PhaseAText")%></td>
                    <td class="tabletextbold" style="width: 240px;text-align:right"><%= LocalString("PhaseBText")%></td>
                    <td class="tabletextbold" style="width: 151px; text-align: right"><%= LocalString("PhasecText")%></td>

                    <td class="tabletextbold" style="width: 240px;text-align:right">Total</td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageABText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousVoltagePhaseAB", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px; text-align: right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageBCText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousVoltagePhaseBC", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageCAText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("InstantaneousVoltagePhaseCA", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageAngleABText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousVoltagePhaseAB", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px; text-align: right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageAngleBCText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousVoltagePhaseBC", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageAngleCAText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("InstantaneousVoltagePhaseCA", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("VoltageHarmonicdistorsionText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousVoltageHarmonicDistortionPhaseA", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousVoltageHarmonicDistortionPhaseB", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("InstantaneousVoltageHarmonicDistortionPhaseC", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("CurrentHarmonicdistorsionText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("IharmPhaseAPV", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("IharmPhaseBPV", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("IharmPhaseCPV", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("DistorsionPowerText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousDistorsivePowerPhaseA", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousDistorsivePowerPhaseB", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("InstantaneousDistorsivePowerPhaseC", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousDistorsivePowerThreePhase", "{0:N4}")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PowerFactorText") %></td>
                    <td style="width: 151px;"></td>
                    <td style="width: 240px;"></td>
                    <td style="width: 151px;"></td>

                    <td style="width: 240px;"></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("ActivePowerText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstActiveKWA1", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstActiveKWB1", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("InstActiveKWC1", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("instKW", "{0:N4}")%></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("ApparentVAText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("VAarithPhaseAPV", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("VAarithPhaseBPV", "{0:N4}")%></td>
                    <td style="width: 151px; text-align: right"><%# Eval("VAarithPhaseCPV", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("InstVArms", "{0:N4}")%></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("ApparentVAPFText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("instPFA1", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("instPFB1", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("instPFC1", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("PFinstAVA", "{0:N4}")%></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("ReactivePowerText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstVARA1", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstVARB1", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstVARC1", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("ArithmeticVARSysPV", "{0:N4}")%></td>
                </tr>

                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("ReactiveVARPFText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%# Eval("PFinstAVAR", "{0:N4}")%></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PhaseorVAText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("PVAPhaseAPV", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("PhaseAPVBI", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("PVAPhaseCPV", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("instVA", "{0:N4}")%></td>
                </tr>
                <tr>

                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PhaseorVAPFText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousCosinePhaseA", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousCosinePhaseA", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstantaneousCosinePhaseA", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("InstantaneousCosineThreePhase", "{0:N4}")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PhaseorVARText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("VARPhaseAPV", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("VARPhaseBPV", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("VARPhaseCPV", "{0:N4}")%></td>

                    <td style="width: 240px;text-align:right"><%# Eval("InstVARTimeDelay", "{0:N4}")%></td>
                </tr>

                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PhaseorVARPFText") %></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%# Eval("PFinstPVAR", "{0:N4}")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("PFAngleText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("PFanglePhaseAPV", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%# Eval("PFanglePhaseBPV", "{0:N4}")%></td>
                    <td style="width: 151px;text-align:right"><%# Eval("PFanglePhaseCPV", "{0:N4}")%></td>   

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("FrequencyText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("InstFREQ", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>

                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                </tr>
                <tr>
                    <td class="tabletextbold" style="width: 240px;"><%= LocalString("TempratureText") %></td>
                    <td style="width: 151px;text-align:right"><%# Eval("temperature", "{0:N4}")%></td>
                    <td style="width: 240px;text-align:right"><%= LocalString("NAText")%></td>
                    <td style="width: 151px;text-align:right"><%= LocalString("NAText") %></td>  

                    <td style="width: 240px;text-align:right">
                        <%= LocalString("NAText")%>
                    </td>
                </tr>
            </table>
        </div>
    </ItemTemplate>
</asp:FormView>

全部的

---

请帮帮我，我做错了什么。

您需要通过查看中的

来访问其
项目模板中的控件

 HtmlTable table = (HtmlTable)DemandDataView.FindControl("tblDemandData");

有两种选择：

备选案文1。（最推荐）-您可以尝试使用Html agility pack API来解析Html文本

备选案文2。使用字符串生成器将代码追加到字符串生成器变量，并将其传递给html代码。样本如下-
如前所述，您应该在表的父控件上使用FindControl（“YourControlID”）。请注意，FindControl只能在一级子控件中迭代，我记得..
这对我有效，请检查此

只需将
添加到标记的顶部
就可以直接从codebehind访问
FormView
中包含的控件，因为它的
NaminContainer
不是页面本身，而是
FormViewItem
。因此，您需要对其使用
FindControl
。由于
FormView
具有多种模式，因此您必须在右侧使用它。访问它的最佳位置是在
FormView.DataBound
中，使用
FormView模式上的
开关
-语句。