The control collection cannot be modified during DataBind, .....

Question

The control collection cannot be modified during DataBind, Init, Load, PreRender or Unload phases.
at System.Web.UI.ControlCollection.Add(Control child)
at AjaxControlToolkit.ScriptObjectBuilder.RegisterCssReferences(Control control)
at System.Web.UI.Control.LoadRecursive()
I am getting the above error for the following code at last line while adding updatepanel to controls collection:
protected override void CreateChildControls()
base.CreateChildControls();
UpdatePanel updatePanel1 = new UpdatePanel();
updatePanel1.ID = "udpItemListingWebPart";
updatePanel1.ChildrenAsTriggers = false;
updatePanel1.UpdateMode = UpdatePanelUpdateMode.Conditional;
this.Controls.Add(updatePanel1);
What am I doing wrong? Thanks for any pointers.

Answer 1

I think you need move your code in preInit or pageload. Also do you have script manager in your page through master page already?
http://forums.asp.net/t/1165939.aspx
http://blogs.msdn.com/b/mikeormond/archive/2007/03/15/dynamically-adding-an-updatepanel-to-your-page.aspx
http://forums.asp.net/t/1184056.aspx?Programmatically+creating+UpdatePanel+and+creating+Triggers
Thanks,
Sohel Rana
http://ranaictiu-technicalblog.blogspot.com