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Old August 31st, 2010, 08:41 AM
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Default Nested controls in UserControl return null (FindControl)

Hi everyone,
I have a very weird issue. I have a UserControl that has some controls inside. I want to refer those controls after, in another postback. But when I try to get them the ".Controls" property of my controls returns null.
I'm working on vs2008
Here is the sample code:
	public partial class MyUserControl : System.Web.UI.UserControl
		protected void Page_Load(object sender, EventArgs e)
			foreach (Control control in this.Controls)

		private void MyTable()
			Table table = new Table();

			TableRow row = new TableRow();
			TableCell cell = new TableCell();

			CheckBox check = new CheckBox();
			check.ID = "theId";
			check.Text = "My Check";
			check.AutoPostBack = true;

			check = new CheckBox();
			check.ID = "theOther";
			check.AutoPostBack = true;
			check.Text = "My Other Check";

			cell = new TableCell();


		protected override void Render(HtmlTextWriter writer)
and in the Default.aspx page is something like:
HTML Code:
<%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Default.cs" Inherits="Tester.Default" %>
<%@ Register TagPrefix="uc1" TagName="MyControl" Src="~/MyUserControl.ascx" %>

<!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>Unbenannte Seite</title>
    <form id="form1" runat="server">
		<uc1:MyControl ID="MyControlInstance" runat="server" />
Idk if I'm lost in somepart of the asp.net lifecycle. But this situation is making me crazy. Any help would be very grateful.
Old September 6th, 2010, 06:46 AM
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Hi there,

Render fires after Load, so your table has not been created yet when you loop over the controls.
Could that be the issue?

Imar Spaanjaars
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Author of Beginning ASP.NET 4.5 : in C# and VB, Beginning ASP.NET Web Pages with WebMatrix
and Beginning ASP.NET 4 : in C# and VB.
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Old September 6th, 2010, 06:56 AM
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Default Yes, It was the asp lifecycle

Yes, you're right:
Here I post some links that helped me to solve the issue.

Thanks for your response.

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