Problem with ScriptManager.RegisterStartupScript in WebControl nested in UpdatePanel
- by Chris
Hello,
I am having what I believe should be a fairly simple problem, but for the life of me I cannot see my problem. The problem is related to ScriptManager.RegisterStartupScript, something I have used many times before.
The scenario I have is that I have a custom web control that has been inserted into a page. The control (and one or two others) are nested inside an UpdatePanel. They are inserted onto the page onto a PlaceHolder:
<asp:UpdatePanel ID="pnlAjax" runat="server">
<ContentTemplate>
<asp:PlaceHolder ID="placeholder" runat="server">
</asp:PlaceHolder>
...
protected override void OnInit(EventArgs e){
placeholder.Controls.Add(Factory.CreateControl());
base.OnInit(e);
}
This is the only update panel on the page.
The control requires some initial javascript be run for it to work correctly. The control calls:
ScriptManager.RegisterStartupScript(this, GetType(),
Guid.NewGuid().ToString(), script, true);
and I have also tried:
ScriptManager.RegisterStartupScript(Page, Page.GetType(),
Guid.NewGuid().ToString(), script, true);
The problem is that the script runs correctly when the page is first displayed, but does not re-run after a partial postback. I have tried the following:
Calling RegisterStartupScript from CreateChildControls
Calling RegisterStartupScript from OnLoad / OnPreRender
Using different combinations of parameters for the first two parameters (in the example above the Control is Page and Type is GetType(), but I have tried using the control itself, etc).
I have tried using persistent and new ids (not that I believe this should have a major impact either way).
I have used a few breakpoints and so have verified that the Register line is being called correctly.
The only thing I have not tried is using the UpdatePanel itself as the Control and Type, as I do not believe the control should be aware of the update panel (and in any case there does not seem to be a good way of getting the update panel?).
Can anyone see what I might be doing wrong in the above?
Thanks :)