How do I return the name (ID) of the User Control that Raised an Event?

[Gummy]

Hello,

I have a user control (contains two listboxes, labels and radio buttons)
that appears on my webpage multiple times. When the radio buttons are
clicked I am able to process (consume?) that Event (SelectedIndexChange) on
the main page.

What I am having a problem with is figuring out which of the user controls
raised that Event. If I know which user control raised the Event I hope to
then refill the listbox with new data.

How do I tell which user control's radio buttons I clicked?

I have this pseudo-code on the main page:
private void WebForm1_SelectedIndexChange(object sender, EventArgs e)
{
DoFunction( User Control Name);
}

I tried sender.GetType().ToString() but that just told me the user control
(UserControl.ascx) and not the actual ID that I assigned to it.

Any help would be greatly appreciated.

Thank you.



p.s. I saw something about a nested Class in the user control that contains
the ID or other information about it, but I certainly don't understand that.