Set Custom ASP.NET UserControl variables when its in a Repeater

Question

<%@ Register Src="~/Controls/PressFileDownload.ascx" TagName="pfd" TagPrefix="uc1" %>

<asp:Repeater id="Repeater1" runat="Server" OnItemDataBound="RPTLayer_OnItemDataBound">
 <ItemTemplate>
   <asp:Label ID="LBLHeader" Runat="server" Visible="false"></asp:Label>
   <asp:Image ID="IMGThumb" Runat="server" Visible="false"></asp:Image>
   <asp:Label ID="LBLBody" Runat="server" class="layerBody"></asp:Label>
   <uc1:pfd ID="pfd1" runat="server" ShowContainerName="false" ParentContentTypeId="55" />
   <asp:Literal ID="litLayerLinks" runat="server"></asp:Literal>
 </ItemTemplate>
</asp:Repeater>

System.Web.UI.WebControls.Label lbl;
System.Web.UI.WebControls.Literal lit;
System.Web.UI.WebControls.Image img;
System.Web.UI.WebControls.HyperLink hl;
System.Web.UI.UserControl uc;

I need to set the ParentItemID variable for the uc1:pdf listed inside the repeater. I thought I should be able to find uc by looking in the e.Item and then setting it somehow. I think this is the part where I'm missing something.

uc = (UserControl)e.Item.FindControl("pfd1");
if (uc != null) { uc.Attributes["ParentItemID"] = i.ItemID.ToString(); }

Any thoughts would be appreciated.

Also tried this with similar results... when I debug inside my usercontrol (pfd1) the parameters I am trying to set have not been set.

uc = (UserControl)e.Item.FindControl("pfd1");
if (uc != null) 
{
  uc.Attributes.Add("ContainerID", _cid.ToString());
  uc.Attributes.Add("ParentItemId", i.ItemID.ToString());
}

UPDATE: It looks like my controls are not connected by a namespace. I've wrapped by the parent control (Layer) and the PressFileDownlad control in a namespace "MyControls". Also updated their Inherits reference on the aspx to read "MyControls.xxxxx". I'm able to type "MyControls.Layer" inside the code on layer.aspx.cs but I'm not able to get "MyControls.PressFileDownload"

Answer 1

If you implement ParentItemID as a public property in your user control, then you should be able to set it declaratively, e.g:

<asp:Repeater id="Repeater1" ...>
 <ItemTemplate>
   <uc1:pfd ID="pfd1" runat="server" ParentItemId='<%# Eval("ItemID") %>' ... />

Answer 2

Martin is right you should be able to set it in declarative way (in case your property is public) . But your way should also work (just cast it properly)

((PressFileDownload)e.Item.FindControl("pfd1")).ParentItemId = 0;

Answer 3

The best way is to implement the OnDataBinding event for the user control. I try to stay away from putting code inline in the aspx using webforms if possible.

When the repeater gets bound, for each item that is bound, the OnDataBinding will fire for your user control and your handler can do what it needs. You don't have to go searching for the controls.

Here is an example:

// in your aspx
<uc1:pfd ID="pfd1" runat="server" ShowContainerName="false" ParentContentTypeId="55"
    OnDataBinding="pfd1_DataBinding" />

// in your codebehind implement the OnDataBinding event
protected void pfd1_DataBinding(object sender, System.EventArgs e)
{
    pfd uc = (pfd)(sender);
    uc.ContainerID = _containerID.ToString();
    uc.ParentItemID = Eval("ItemID");

    // Here you can do more like access other items like hidden fields
    // or cached objects or even other controls etc... Skys the limit.
} 

EDIT: Notice from your comment you require more data than what is found in the datasource. In this case what I usually do is just make private member variables in the .cs that I store data in. So when you have the container ID just store it in a variable that will be accessible.

Eg in your .cs for your page:

public partial class _TestPage : System.Web.UI.Page
{
    private int _containerID { get; set; }

Then when you load the data just set the _containerID property and it will be accessible in the OnDataBinding event. Just make sure you are binding after you have set the _containerID.