Binding a web user control in another ContentPlaceHolder

Posted on 2006-07-18
Last Modified: 2008-01-09
I have a master page with multiple ContentPlaceHolders. The first one contains a web user control of class Controls_CategorySelector. The second one contains a data source, and one of its parameters is bound to the SelectedCategory property of the CategorySelector. How can this binding be done without compilation error?

<asp:Content ID="Content1" ContentPlaceHolderID="LeftMenuHolder" runat="Server">
    <uc1:CategorySelector ID="catSelector" runat="server" OnLoad="CategorySelectorLoad"/>    

<asp:Content ID="Content2" ContentPlaceHolderID="ContentHolder" runat="Server">
    <asp:SqlDataSource ID="ArticleDataSource" runat="server" ConnectionString="<%$ ConnectionStrings:RTFMConnectionString %>"
        SelectCommand="listRecentArticles" SelectCommandType="StoredProcedure">
            <asp:ControlParameter ControlID="catSelector" DefaultValue="0" Name="categoryId"
                PropertyName="SelectedCategory" Type="Int32" />

The ControlID "catSelector" is only found by the compiler if the data source and the CategorySelector are in the same ContentPlaceHolder.
Question by:pallosp
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LVL 96

Expert Comment

by:Bob Learned
ID: 17129733
What is 'CategorySelector' defined as?


Author Comment

ID: 17130003
It is a RadioButtonList populated from code. The category ID belonging to the SelectedIndex property is led out as SelectedCategory.
LVL 96

Expert Comment

by:Bob Learned
ID: 17131211
I was trying to figure out what uc1:CategorySelector was, and it doesn't sound like a RadioButtonList.  Is it a third-party control, or a home-grown custom web control?

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Author Comment

ID: 17132459
Here is a simple code without web user controls that produce the same phenomenon:


<%@ Master Language="C#" AutoEventWireup="true" CodeFile="MasterPage.master.cs" Inherits="MasterPage" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "">
<html xmlns="">
<head runat="server">
    <title>Untitled Page</title>
    <form id="form1" runat="server">
            <asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server"></asp:ContentPlaceHolder>
            <asp:ContentPlaceHolder ID="ContentPlaceHolder2" runat="server"></asp:ContentPlaceHolder>


<%@ Page Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="true"
    CodeFile="Default.aspx.cs" Inherits="_Default" Title="Untitled Page" %>

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder2" runat="Server">
    <asp:TextBox ID="TextBox1" runat="server"></asp:TextBox>
    <asp:GridView ID="GridView1" runat="server" DataSourceID="ObjectDataSource1">
    <asp:ObjectDataSource ID="ObjectDataSource1" runat="server" SelectMethod="GetItems"
            <asp:ControlParameter ControlID="TextBox1" Name="prefix" PropertyName="Text" Type="String" />


public class Class1
    public static string[] GetItems(string prefix) {
        return new string[] { prefix+"1", prefix+"2" };

After TextBox1 had been moved to the first ContentPlaceHolder, the code didn't compile.
LVL 96

Expert Comment

by:Bob Learned
ID: 17132939
It compiled for me with TextBox1 under Context1.  I created a Web Site model type web site, and I don't know which type you created.  But, I can't see where that would cause a problem.

LVL 96

Accepted Solution

Bob Learned earned 500 total points
ID: 17132978
Aaah, yes, it's a run-time exception:

    Could not find control 'TextBox1' in ControlParameter 'prefix'.

Try this:

            <asp:ControlParameter ControlID="ContentPlaceHolder1$TextBox1" Name="prefix" PropertyName="Text" Type="String" />


Author Comment

ID: 17133370
Big thanks!

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