在JavaScript中获取asp.net控件的ID

Question

我正在ASP.Net应用程序中工作，需要获取某些客户端控件的ID。我曾尝试以下，但不断收到错误：

<script type="text/javascript"> 
    var cbDeclinedID = '<%= cbDeclined.ClientID %>'; 
</script> 

不要紧，我把这个代码，我总是得到错误：

CS0103：“cbDeclined”名称不存在当前上下文

的标记：

<%@ Page Title="Manage Resident Meals" Language="C#" MasterPageFile="~/Site.Master" AutoEventWireup="true" CodeBehind="ManageResidentMeals.aspx.cs" Inherits="Chart2GoWeb.WebUI.WebForms.ManageResident.ManageResidentMeals" %> 

<asp:Content ID="jsContent" ContentPlaceHolderID="JavaScriptContent" runat="server"> 

<script type="text/javascript"> 
<!-- 
    // var cbDeclinedID = '< %= cbDeclined.ClientID % >'; 

    function NumericOnly() { var key = window.event.keyCode; if (key < 48 || key > 57) window.event.returnValue = false; } 

    $(document).ready(function() { 
     function UpdateTextBoxes(isDeclined, isNOP, isOutOfFac) { 
      var ddlMealReplacement = $('#ddlMealReplacement'); 

      var lblMealOld = $('#lblMealOld'); 
      var lblFortifiedFluidOld = $('#lblFortifiedFluidOld'); 
      var lblFluidOld = $('#lblFluidOld'); 

      var txtMeal = $('#txtMeal'); 
      var txtFluid = $('#txtFluid'); 
      var txtFortifiedFluid = $('#txtFortifiedFluid'); 

      var mealReplacement = ''; 
      if (ddlMealReplacement.length) { 
       mealReplacement = ddlMealReplacement.text(); 
      } 

      if (isNOP || (isDeclined && mealReplacement != 'G')) { 
       txtMeal.prop('disabled', true); 
       txtMeal.val(''); 
       lblMealOld.val('___'); 
      } else { 
       txtMeal.prop('disabled', false); 
      } 

      // txtFluid.Enabled = !isNOP; 
      txtFluid.prop('disabled', isNOP); 
      // txtFortifiedFluid.Enabled = !isNOP; 
      txtFortifiedFluid.prop('disabled', isNOP); 

      if (isNOP) { 
       txtFluid.val(''); 
       txtFortifiedFluid.val(''); 
       $('#lblFluidTotalString').val(''); 
      } 
     } 

     function Total(lblFluidTotal, val1, val2) { 
      var totalFluids = null; 

      var num = parseFloat(val1); 
      if (num != 'NaN') 
       totalFluids = val1Num; 

      num = parseFloat(val2); 
      if (num != 'NaN') 
       totalFluids = (totalFluids == null) ? num : num + totalFluids; 

      if (totalFluids == null) 
       lblFluidTotal.val('___'); 
      else 
       lblFluidTotal.val(totalFluids); 
     } 

     $('#'+cbDeclinedID).click(function() { 
      var cbDeclined = $(this); 
      var cbIsOutOfFac = $('#cbIsOutOfFac'); 
      var cbNOP = $('#cbNOP'); 

      if (cbDeclined.is(':checked')) 
       cbIsOutOfFac.attr('checked', false); 

      UpdateTextBoxes(cbDeclined.is(':checked'), cbNOP.is(':checked'), cbIsOutOfFac.is(':checked')); 
     }); 

     $('#cbIsOutOfFac').click(function() { 
      var cbDeclined = $('#cbDeclined'); 
      var cbIsOutOfFac = $(this); 
      var cbNOP = $('#cbNOP'); 

      UpdateTextBoxes(cbDeclined.is(':checked'), cbNOP.is(':checked'), cbIsOutOfFac.is(':checked')); 
     }); 

     $('#cbNOP').click(function() { 
      var cbDeclined = $('#cbDeclined'); 
      var cbIsOutOfFac = $('#cbIsOutOfFac'); 
      var cbNOP = $(this); 

      UpdateTextBoxes(cbDeclined.is(':checked'), cbNOP.is(':checked'), cbIsOutOfFac.is(':checked')); 
     }); 

     $('#ddlMealReplacement').change(function() { 
      var cbDeclined = $('#cbDeclined'); 
      var cbIsOutOfFac = $('#cbIsOutOfFac'); 
      var cbNOP = $('#cbNOP'); 

      UpdateTextBoxes(cbDeclined.is(':checked'), cbNOP.is(':checked'), cbIsOutOfFac.is(':checked')); 
     }); 

     $('#txtFluid').change(function() { 
      var txtFluid = $(this); 
      var txtFortifiedFluid = $('#txtFortifiedFluid'); 
      var lblFluidTotal = $('#lblFluidTotal'); 

      Total(lblFluidTotal, txtFluid.val(), txtFortifiedFluid.val()); 
     }); 

     $('#txtFortifiedFluid').change(function() { 
      var txtFluid = $('#txtFluid'); 
      var txtFortifiedFluid = $(this); 
      var lblFluidTotal = $('#lblFluidTotal'); 

      Total(lblFluidTotal, txtFluid.val(), txtFortifiedFluid.val()); 
     }); 
    }); 

    //--> 
    </script> 

</asp:Content> 

<asp:Content ID="Content1" ContentPlaceHolderID="HeadContent" runat="server"> 
</asp:Content> 

<asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> 

    <asp:ObjectDataSource ID="ResidentsMealsODS" runat="server" 
     InsertMethod="InsertNourishment"   
     SelectMethod="GetMealsDetailByResMealInTakeId" 
     TypeName="Chart2GoWeb.Domain.DAL.ResidentsMealsDAL" 
     UpdateMethod="UpdateNourishment" 
     > 

     <SelectParameters> 
      <asp:SessionParameter DefaultValue="" Name="session" SessionField="__MySession__" Type="Object" /> 
      <asp:QueryStringParameter Name="resMealInTakeIdString" QueryStringField="resMealInTakeId" Type="String" /> 
      <asp:QueryStringParameter Name="nourishment" QueryStringField="nourishmentType" Type="String" /> 
     </SelectParameters> 

     <InsertParameters> 
      <asp:SessionParameter DefaultValue="" Name="session" SessionField="__MySession__" Type="Object" /> 
      <asp:QueryStringParameter Name="resMealInTakeIdString" QueryStringField="resMealInTakeId" Type="String" /> 
      <asp:QueryStringParameter Name="nourishment" QueryStringField="nourishmentType" Type="String" /> 
      <asp:Parameter Name="IsDeclined" Type="String"/> 
      <asp:Parameter Name="IsOutOfFac" Type="String"/> 
      <asp:Parameter Name="IsNpo" Type="String"/> 
      <asp:Parameter Name="MealReplacement" Type="string"/> 
      <asp:Parameter Name="Pct" Type="String"/> 
      <asp:Parameter Name="Fluid" Type="String"/> 
      <asp:Parameter Name="FortifiedFluid" Type="String"/> 
      <asp:Parameter Name="FluidTotal" Type="String"/> 
      <asp:Parameter Name="TubeFeeding" Type="String" /> 
     </InsertParameters> 

     <UpdateParameters> 
      <asp:SessionParameter DefaultValue="" Name="session" SessionField="__MySession__" Type="Object" /> 
      <asp:QueryStringParameter Name="resMealInTakeIdString" QueryStringField="resMealInTakeId" Type="String" /> 
      <asp:QueryStringParameter Name="nourishment" QueryStringField="nourishmentType" Type="String" /> 
      <asp:Parameter Name="IsDeclined" Type="String"/> 
      <asp:Parameter Name="IsOutOfFac" Type="String"/> 
      <asp:Parameter Name="IsNpo" Type="String"/> 
      <asp:Parameter Name="MealReplacement" Type="String"/> 
      <asp:Parameter Name="Pct2EditBind" Type="String"/> 
      <asp:Parameter Name="Fluid2EditBind" Type="String"/> 
      <asp:Parameter Name="FortifiedFluid2EditBind" Type="String"/> 
      <asp:Parameter Name="TubeFeeding" Type="String" /> 
     </UpdateParameters> 

    </asp:ObjectDataSource> 

    <asp:ObjectDataSource ID="MealReplacementOptionDataSource" runat="server" 
     TypeName="Chart2GoWeb.Domain.Entities.WFEvents.MealReplacementOption" 
     SelectMethod="Select"> 
    </asp:ObjectDataSource> 

    <asp:FormView 
     DataSourceID="ResidentsMealsODS" 
     ID="nourishmentFormView" 
     DefaultMode="Edit" 
     OnItemInserted="nourishment_OnItemInserted" 
     OnItemUpdated="nourishment_OnItemUpdated" 
     RunAt="server"> 
     <EditItemTemplate> 

     <table class="EventQtable"> 
      <tr> 
       <th colspan="2"> 
        <asp:Label ID="Title" runat="server"><% Response.Write(TitleString); %></asp:Label> 
       </th> 
      </tr> 
      <tr> 
       <td>Date</td> 
       <td><asp:Label ID="mealDate" runat="server" Text='<%# Eval("MealDate") %>'/></td> 
      </tr> 
      <tr> 
       <td>Declined</td> 
       <td><asp:CheckBox ID="cbDeclined" runat="server" Checked='<%# Bind("IsDeclined") %>' /></td> 
      </tr> 
      <tr> 
       <td>Out Of Facility</td> 
       <td><asp:CheckBox ID="cbIsOutOfFac" runat="server" Checked='<%# Bind("IsOutOfFac") %>'/></td> 
      </tr> 
      <tr> 
       <td>NPO</td> 
       <td><asp:CheckBox ID="cbNPO" runat="server" Checked='<%# Bind("IsNpo") %>'/></td> 
      </tr> 
<% 
    // Only show the meal replacement if the nourishment type does NOT have an underscore in it. 
    if (Request.QueryString["nourishmentType"].IndexOf('_') == -1) 
    { 
%> 
      <tr> 
       <td> 
        Meal Replacement</td> 
       <td> 
        <asp:DropDownList ID="ddlMealReplacement" runat="server" AutoPostBack="True" 
         DataSourceID="MealReplacementOptionDataSource" DataTextField="DisplayValue" 
         DataValueField="DBValue"       
         SelectedValue='<%# Bind("MealReplacement") %>' /> 
       </td> 
      </tr> 
<% 
    } 
%> 
      <tr> 
       <td>Meal</td> 
       <td> 
        <asp:Label ID="lblMealOld" runat="server" CssClass="ccUnits" Text='<%# Eval("Pct4Edit") %>' />% + 
        <asp:TextBox ID="txtMeal" runat="server" type="number" CssClass="ccUnits" MaxLength="3" OnKeyPress="NumericOnly()" Text='<%# Bind("Pct2EditBind") %>' />%<asp:RangeValidator ID="rvRangeValidator" runat="server" ControlToValidate="txtMeal" ErrorMessage="Valid range is 0-200" MaximumValue="200" MinimumValue="0" Type="Integer">*</asp:RangeValidator> 
       </td> 
      </tr> 
      <tr> 
       <td>Fluid</td> 
       <td> 
        <asp:Label ID="lblFluidOld" runat="server" CssClass="ccUnits" Text='<%# Eval("Fluid4Edit") %>' />cc + 
        <asp:TextBox ID="txtFluid" runat="server" type="number" CssClass="ccUnits" MaxLength="4" OnKeyPress="NumericOnly()" Text='<%# Bind("Fluid2EditBind") %>' />cc 
       </td> 
      </tr> 
      <tr> 
       <td>Fortified Fluid</td> 
       <td> 
        <asp:Label ID="lblFortifiedFluidOld" runat="server" CssClass="ccUnits" Text='<%# Eval("FortifiedFluid4Edit") %>' />cc + 
        <asp:TextBox ID="txtFortifiedFluid" runat="server" type="number" CssClass="ccUnits" MaxLength="4" OnKeyPress="NumericOnly()" Text='<%# Bind("FortifiedFluid2EditBind") %>' />cc 
       </td> 
      </tr> 
      <tr> 
       <td>Fluid Total</td> 
       <td> 
        <asp:Label ID="lblFluidTotal" runat="server" CssClass="ccUnits" Text='<%# Eval("FluidTotal4Edit") %>' />cc 
       </td> 
      </tr> 
     </table> 
     <asp:Button ID="saveButton" runat="server" CommandName="Update" CssClass="GenBtn" Text="Save" />&nbsp; 
     <asp:Button ID="cancelButton" runat="server" CssClass="GenBtn" onclick="cancelButton_Click" Text="Cancel" /> 
     </EditItemTemplate> 



     <InsertItemTemplate> 
     <table class="EventQtable"> 
      <tr> 
       <th colspan="2"><asp:Label ID="Title" runat="server"><% Response.Write(TitleString); %></asp:Label></th> 
      </tr> 
      <tr> 
       <td>Date</td> 
       <td><asp:Label ID="mealDate" runat="server" Text='<%# Eval("MealDate") %>'/></td> 
      </tr> 
      <tr> 
       <td>Declined</td> 
       <td><asp:CheckBox ID="cbDeclined" runat="server" Checked='<%# Bind("IsDeclined") %>'/></td> 
      </tr> 
      <tr> 
       <td>Out Of Facility</td> 
       <td><asp:CheckBox ID="cbIsOutOfFac" runat="server" Checked='<%# Bind("IsOutOfFac") %>'/></td> 
      </tr> 
      <tr> 
       <td>NPO</td> 
       <td><asp:CheckBox ID="cbNPO" runat="server" Checked='<%# Bind("IsNpo") %>'/></td> 
      </tr> 
<% 
    // Only show the meal replacement if the nourishment type does NOT have an underscore in it. 
    if (Request.QueryString["nourishmentType"].IndexOf('_') == -1) 
    { 
%> 
      <tr> 
       <td>Meal Replacement</td> 
       <td><asp:DropDownList ID="ddlMealReplacement" runat="server" AutoPostBack="True" 
             DataSourceID="MealReplacementOptionDataSource" DataTextField="DisplayValue" 
             DataValueField="DBValue" 
             SelectedValue='<%# Bind("MealReplacement") %>' /></td> 
      </tr> 
<% 
    } 
%> 
      <tr> 
       <td>Meal</td> 
       <td> 
        <asp:Label ID="lblMealOld" runat="server" Text="0" CssClass="ccUnits"/>%&nbsp; + 
        <asp:TextBox ID="txtMeal" runat="server" type="number" Text='<%# Bind("Pct") %>' MaxLength="3" OnKeyPress="NumericOnly()" CssClass="ccUnits" />%<asp:RangeValidator ID="rvRangeValidator" runat="server" ErrorMessage="Valid range is 0-200" Type="Integer" MaximumValue="200" MinimumValue="0" ControlToValidate="txtMeal">*</asp:RangeValidator> 
       </td> 
      </tr> 
      <tr> 
       <td>Fluid</td> 
       <td> 
        <asp:Label ID="lblFluidOld" runat="server" Text="0" CssClass="ccUnits"/>cc + 
        <asp:TextBox ID="txtFluid" runat="server" type="number" Text='<%# Bind("Fluid") %>' MaxLength="4" OnKeyPress="NumericOnly()" CssClass="ccUnits" />cc 
       </td> 
      </tr> 
      <tr> 
       <td>Fortified Fluid</td> 
       <td> 
        <asp:Label ID="lblFortifiedFluidOld" runat="server" Text="0" CssClass="ccUnits" Enabled="false" />cc + 
        <asp:TextBox ID="txtFortifiedFluid" runat="server" type="number" Text='<%# Bind("FortifiedFluid") %>' MaxLength="4" OnKeyPress="NumericOnly()" CssClass="ccUnits" />cc 
       </td> 
      </tr> 
      <tr> 
       <td>Fluid Total</td> 
       <td> 
        <asp:Label ID="lblFluidTotal" runat="server" Text='0' CssClass="ccUnits"/>cc 
       </td> 
      </tr> 
     </table> 
     <asp:Button ID="saveButton" CssClass="GenBtn" runat="server" Text="Save" CommandName="Insert"/>&nbsp; 
     <asp:Button ID="cancelButton" CssClass="GenBtn" runat="server" Text="Cancel" onclick="cancelButton_Click"/> 

     </InsertItemTemplate> 
    </asp:FormView> 

<script type="text/javascript"> 
    var cbDeclinedID = '<%= cbDeclined.ClientID %>'; 
</script> 

</asp:Content> 

<asp:Content ID="Content3" ContentPlaceHolderID="FooterContent" runat="server"> 
    <table class="footer" border="0" cellspacing="0" cellpadding="0" style="background-image: url('<%= ResolveClientUrl("~/Images/BottomBar-1000x42.png")%>'); background-repeat: no-repeat; height: 42px; width: 1000px;" > 
     <tr> 
      <td width="4%">&nbsp;</td> 
      <td width="9%"></td> 
      <td width="56%">&nbsp;</td> 
      <td width="27%" align="center"/> 
      <td width="4%"></td> 
     </tr> 
    </table> 
</asp:Content> 

Answer 1

这是因为dbDeclines是内定义您的<asp:FormView id="nourishmentFormView">的模板。

试试这个（未经测试）...

<script type="text/javascript"> 
    var cbDeclinedID = '<%=nourishmentFormView.FindControl("cbDeclined").ClientID%>'; 
</script> 

Answer 2

愚蠢的问题，但确实存在cbDeclined？

如果是这样，是否可能在另一个控件（即gridview或listview），然后需要你获得网格，然后.GetChildControl（），而不是直接引用cbDeclined？

你现在这样做的方式是在ASP.NET中引用一个ID的正确方法（除非你使用静态可猜测的ID，但是打破了功能的重复控制）。

编辑

更新的代码后，你似乎是tryign引用另一个控件内部控制，你需要做的是这样

<script type="text/javascript"> 
    var cbDeclinedID = '<%= ((CheckBox)nourishmentFormView.FindControl("cbDeclined")).ClientID %>'; 
</script>