Pass data to user components in asp.net

It is .net 2.0 here, not MVC, and I am crap at asp forms.

I have a page with user controls on it. When I click on something in the page, I want to load the usercontrol based on a parameter from the page.

I cannot do it.

In my page's FaultTree_Clicked, I get the value, then:

I tried exposing a property on the child user control to set the value, which i set in FaultTree_Clicked, it gets forgotten.
I tried saving it to Session["mykey"], and loading Session["mykey"] in the control's Page_init... the value is blank.
I tried saving it to ViewState["mykey"], and loading ViewState["mykey"] in the control's Page_init... the value is blank.

EDIT: more specific info:

Here is a cut down version of what the page(MyFault) looks like:

<form id="form" runat="server">
 <div id="faulttree">
   <asp:TreeView ID="FaultTree" ......>
 </div>
 <uc1:_DefectDetail ID="DefectDetail" runat="server" Visible="true" EnableViewState="true" />
</form>

And there is a method on the pages code behind "FaultTree_SelectedNodeChanged()".

When that method is hit, I want to load/show the DefectDetail control. The DefectControl requires a faultid, which comes off the Tree, which I successfully get in the SelectedNodeChanged method. I cannot get the faultid into the defect control.

Solution

This has to do with ASP.NET page lifecycle. By the time the click event fires, the control's init event has already happened.

In order to better assist you, please provide a more detailed explanation of what the FaultTree control is, what is the desired result and some sample code.

UPDATE:

Instead of a public property, you can simply create a public method in the control that does the desired action and invoke it from the FaultTree_SelectedNodeChangeEvent.

Example (for a public method named Refresh):

_DefectDetail.Refresh(object data);