Design-time error - multiple controls with the same ID
I am using VS 2008, I have a very simple page with lots of uniquely named controls. When I try to view it in design mode, I get the following error:
Error Rendering Control - Label12
An unhanded exception has occurred.
Multiple controls with the same ID 'Label1' were found. FindControl requires that controls have unique IDs
I checked the HTML and designer file and I can only see one control called Label1. What could be causing this?
Also, here is the aspx markup I am running into?
<%@ Page Language="vb" AutoEventWireup="false" CodeBehind="CoachingAppearanceReport.aspx.vb"
Inherits="AcademyPro.CoachingAppearanceReport" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
</head>
<body>
<form id="form1" runat="server">
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<div id="appearanceDetail" class="Left CriteriaContainer">
<asp:Label ID="Label1" runat="server" Text="Appearance Type" AssociatedControlID="ddlAppearanceType" />
<asp:DropDownList ID="ddlAppearanceType" runat="server" CssClass="AppType" OnDataBound="ddlAppearanceType_DataBound"
DataSourceID="odsAppearanceType" DataTextField="AppearanceType" DataValueField="AppearanceTypeCode">
</asp:DropDownList>
<asp:RequiredFieldValidator ID="rfvAppearanceType" runat="server"
ControlToValidate="ddlAppearanceType" InitialValue="" Text="*"
ErrorMessage="The appearance type must be selected" />
<asp:Label ID="lblAppearanceType" runat="server" />
<br />
<div class="SubSettings">
<asp:Label ID="Label12" runat="server" Text="Subbed for" AssociatedControlID="ddlSubbedFor" />
<asp:DropDownList ID="ddlSubbedFor" runat="server" OnDataBound="ddlSubbedFor_DataBound"
DataSourceID="odsPlayersInAgeGroup" DataTextField="PlayerName" DataValueField="PlayerID">
</asp:DropDownList>
<asp:Label ID="lblSubbedFor" runat="server" />
<br />
<asp:Label ID="Label13" runat="server" Text="Mins" AssociatedControlID="txtSubMins" />
<asp:TextBox ID="txtSubMins" runat="server" MaxLength="3" CssClass="TinyWidth" />
<asp:Label ID="lblSubMins" runat="server" />
</div>
</div>
</ContentTemplate>
</asp:UpdatePanel>
</form>
</body>
</html>
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Is this a "web application project"?
It is possible that your file is .designer.cs
corrupted / outdated and has two copies of "Label1" inside it, which could cause problems.
If so, delete the contents of the file " .designer.cs
" and return to your markup. Add a line line after the file header line, save the page, and then remove the line and save the page. This will re-generate the constructor, which may solve the problem.
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