protected internal override void Render (HtmlTextWriter writer) {
writer.AddAttribute (HtmlTextWriterAttribute.Id, ClientID);
if (RenderMode == UpdatePanelRenderMode.Block)
writer.RenderBeginTag (HtmlTextWriterTag.Div);
else
writer.RenderBeginTag (HtmlTextWriterTag.Span);
RenderChildren (writer);
writer.RenderEndTag ();
}