Unable to find control in asp.net Repeater control

asp.netfindcontrolrepeater

This has got me stumped. I am trying to find a checkbox in a dynamically loaded asp.net Repeater template. The template works fine and the databinding is fine and everything displays fine but I can't find the control! Any ideas?

This is the repeater code (I have a similar one for the alternate template with a different style):

<%@ Control Language="C#" AutoEventWireup="true" CodeFile="template-tasks-

incomplete.ascx.cs" Inherits="controls_template_tasks_incomplete" %>
<ItemTemplate>
    <div class="task">
        <div class="date"><asp:CheckBox ID="chkIsComplete" runat="server" 
                AutoPostBack="True" /><%# DataBinder.Eval(((RepeaterItem)Container).DataItem, "DateCreated")%></div>
        <div class="description"><%# DataBinder.Eval(((RepeaterItem)Container).DataItem, "TaskDescription")%></div>
    </div>                    
</ItemTemplate>

This is how I load the templates (works fine)

rptTasks.ItemTemplate = LoadTemplate("~/controls/template-tasks-incomplete.ascx");
        rptTasks.AlternatingItemTemplate = LoadTemplate("~/controls/template-tasks-incomplete-alt.ascx");

…and finally this is how I try to find the checkbox (but keeps coming up null)

protected void rptTasks_ItemDataBound(object sender, RepeaterItemEventArgs e)
{
    if (e.Item.ItemType == ListItemType.AlternatingItem || e.Item.ItemType == ListItemType.Item)
    {
        CheckBox chkBoxIsComplete = (CheckBox)e.Item.FindControl("chkIsComplete");

        if (chkBoxIsComplete != null)
        {
            int taskID = (int)DataBinder.Eval(e.Item.DataItem, "TaskID");
        }
    }
}

I can only think the checkbox is buried deeper in the hierarchy somewhere, but I'm not sure how to access it as I thought FindControl would do it.

This is the HTML that's generated:

<ItemTemplate>
<div class="task">
    <div class="date"><input id="ctl00_ContentPlaceHolder1_rptTasks_ctl00_ctl00_chkIsComplete" type="checkbox" name="ctl00$ContentPlaceHolder1$rptTasks$ctl00$ctl00$chkIsComplete" onclick="javascript:setTimeout('__doPostBack(\'ctl00$ContentPlaceHolder1$rptTasks$ctl00$ctl00$chkIsComplete\',\'\')', 0)" />23/08/2010 11:53:00 PM</div>
    <div class="description">test task</div>
</div>

Best Answer

I have this extension method as part of my toolkit:

    /// <summary>
    /// find the control with the given ID, recursively below the root
    /// </summary>
    public static Control FindControlRecursive( this ControlCollection root, string id )
    {
        foreach ( Control control in root )
        {
            if ( control != null && id.Equals( control.ID, StringComparison.InvariantCultureIgnoreCase ) )
            {
                return control;
            }
            else
            {
                Control result = FindControlRecursive( control.Controls, id );
                if ( result != null )
                {
                    return result;
                }
            }
        }

        return null;
    }

usage:

CheckBox chkBoxIsComplete = (CheckBox)e.Item.Controls.FindControlRecursive("chkIsComplete");
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