How to databind a local variable in an ASPX template? - asp.net

Question

I have a UserControl named SlidingScaleTableReadonly with a bindable public member ScaleEntries, which take a List of struct instances. In the parent page, these lists are stored in a dictionary (InsulinSlidingScaleProtocolEntries), and I must render one SlidingScaleTableReadonly for each entry in this dictionary. Here's my template code so far:
<%# Register TagPrefix="uc" TagName="SlidingScaleTableReadonly" Src="~/Patient/SlidingScaleTableReadonly.ascx" %>
<asp:Content ContentPlaceHolderID="phContent" runat="server">
<h1>Échelles</h1>
<% For Each drug In InsulinSlidingScaleProtocolEntries %>
<h2><%= drug.Key %></h2>
<uc:SlidingScaleTableReadonly runat="server" ScaleEntries="<%# drug.Value %>" />
<% Next %>
</asp:Content>
My problem is at line 7:
BC30451 'drug' is not declared. It may be inaccessible due to its protection level.
If I replace drug.Value with a property available in code behind, the new variable can be found. I'm guessing it's not possible to directly data-bind local variables in ASPX? If that's the case, how can I use data-binding inside an iteration?
Edit - Changing the provenance of the bound value
I've changed the code a bit. Right after the "For Each" loop opening, a code-behind property named CurrentDrug is reassigned with the value of drug.Value, and uc:SlidingScaleTableReadonly get it's ScaleEntry from that new property. But that doesn't work either, the reassignment won't do shuck and ScaleEntry is always Nothing (or whatever initial value I gave to CurrentDrug).
Here's the new template:
<%# Register TagPrefix="uc" TagName="SlidingScaleTableReadonly" Src="~/Patient/SlidingScaleTableReadonly.ascx" %>
<asp:Content ContentPlaceHolderID="phContent" runat="server">
<h1>Échelles</h1>
<% For Each drug In InsulinSlidingScaleProtocolEntries
CurrentDrug = drug.Value %>
<h2><%= drug.Key %></h2>
<uc:SlidingScaleTableReadonly runat="server" ScaleEntries="<%# CurrentDrug %>" />
<% Next %>
</asp:Content>
And code-behind:
Public CurrentDrug As List(Of ScaleEntry)
Public Property InsulinSlidingScaleProtocolEntries As Dictionary(Of String, List(Of ScaleEntry))
'...
End Property
Edit - (Not) a solution: Stopped using aspx templates
I have to move on, and it seems like I'm not going to do any progress with aspx templates. I've rewritten the page so the UserControl is declared and inserted in code-behind. I think that's not how one should build an interface, that's not where that kind of logic should be place but I really want to move on.
Here's the new template code:
<asp:Content ContentPlaceHolderID="phContent" runat="server">
<h1>Échelles</h1>
<div id="scaleContainer" runat="server"></div>
</asp:Content>
Code-behind:
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
For Each prescription In InsulinSlidingScaleProtocolEntries
Dim label As New HtmlGenericControl("h2") With {
.InnerText = prescription.Key
}
Dim table = CType(Page.LoadControl("~/Patient/SlidingScaleTableReadonly.ascx"), SlidingScaleTableReadonly)
table.ScaleEntries = prescription.Value
scaleContainer.Controls.Add(label)
scaleContainer.Controls.Add(table)
Next
End Sub
If you have a better solution, I'll be happy to see it.