Question

The title is not entirely accurate, I have a Container control with a property of type PanelControlCollection which is basically a collection of PanelControl:

public class PanelControl : System.Web.UI.WebControls.Panel
{
    public string Title { get; set; }
}

public class PanelControlCollection : Collection<PanelControl> {}

My custom User Control:

public partial class FormSlideShow : BaseUserControl
{
    [PersistenceMode(PersistenceMode.InnerProperty)]
    public PanelControlCollection Panels Title { get; set; }

    protected override void Render(HtmlTextWriter writer)
    {
        foreach(var panel in Panels)
        {
            ContentPlaceHolder.Controls.Add(
                new LiteralControl("<fieldset class='step' Title='" + panel.Title + "'>"));
            ContentPlaceHolder.Controls.Add(panel);
            ContentPlaceHolder.Controls.Add(
                new LiteralControl("</fieldset>"));
        }
        base.Render(writer);
    }
}

I wanted to be able to make a custom control and add pages in markup (code in Default.aspx):

<ctrl:FormSlide runat="server" ID="frmSlide">
    <Panels>
        <ctrl:PanelControl runat="server" ID="page1"><asp:Button runat="server" ID="btnTest" OnClick="btnTest_Onclick" /></ctrl:PanelControl>
        <ctrl:PanelControl runat="server" ID="PanelControl1">Page 2</ctrl:PanelControl>
    </Panels>
</ctrl:FormSlide>

My question is, if I want to host the control in a normal aspx page, how can I connect my Button control (btnTest) to the OnClick event in the code behind of default.aspx? If I put a normal Panel control with a button I can attach events to the onclick but not with my custom control.

btw here is my code behind on default.aspx, the code which I want to run but can’t:

protected void btnTest_Onclick(object sender, EventArgs e)
{
    Response.Redirect("http://www.google.com");
}

Thanks.

Answer 1

Try moving this:

foreach(var panel in Panels)
{
    ContentPlaceHolder.Controls.Add(
        new LiteralControl("<fieldset class='step' Title='" + panel.Title + "'>"));
    ContentPlaceHolder.Controls.Add(panel);
    ContentPlaceHolder.Controls.Add(
        new LiteralControl("</fieldset>"));
}
base.Render(writer);

into OnInit rather than Render. I think Render is too late to register PostBack events with ASP.NET. I was able to reproduce your issue and then resolve it by moving that piece of code.

Of course, base.Render(writer); should be replaced with base.OnInit(e);