How to read a dataitem from a parent repeater? - asp.net

Question

How to read a dataitem from a parent repeater?
<asp:Repeater ID="rpt" runat="Server">
<ItemTemplate>
<%# DataBinder.Eval(Container.DataItem, "MyRepeaterDataItem")%>
<asp:GridView ID="gv" runat="Server">
<Columns>
<asp:TemplateField>
<HeaderTemplate>
<%# DataBinder.Eval(Container.DataItem, "MyRepeaterDataItem")%>
</HeaderTemplate>
<ItemTemplate>
TEXT
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
</ItemTemplate>
</asp:Repeater>
I am trying to get the dataitem MyRepeaterDataItem belonging to the repeater to appear in the nested gridviews header.
I have tried using .Parent and .NamingContainer but cannot get the correct syntax using VB.NET

Answer 1

Assuming you're binding a Datasource to the GridView in the RepeaterItem's ItemDataBound Event Handler you can wire up a Handler for the RowCreated (or DataBound) Events of the GridView using AddHandler:
Private Sub rpt_ItemDataBound(sender As Object, e As RepeaterItemEventArgs) Handles rpt.ItemDataBound
If e.Item.ItemType = ListItemType.AlternatingItem OrElse e.Item.ItemType = ListItemType.Item Then
AddHandler gvTarget.RowCreated, AddressOf GridViewRowCreated
'Bind your Datasource to the GridView AFTER you wire it up:
'Dim gvTarget As GridView = CType(e.Item.FindControl("gv"), GridView)
'gvTarget.DataSource = lstYourDataSource
'gvTager.DataBind()
End If
End Sub
Then your Event Handler for gv's RowCreated can get the value from the parent RepeaterItem:
Public Sub GridViewRowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)
Dim lblHeader As Label = CType(e.Row.FindControl("lblGridViewHeader"), Label)
'Check due to Header/Footer.
If Not lblHeader Is Nothing Then
lblHeader.Text = DataBinder.Eval(CType(sender.Parent, RepeaterItem).DataItem, "MyRepeaterDataItem")
End If
End Sub
The code mentioned above requires you to add a label to your GridView's HeaderTemplate:
<asp:GridView ID="gv" runat="Server">
<Columns>
<asp:TemplateField>
<HeaderTemplate>
<asp:Label ID="lblGridViewHeader" runat="server"></asp:Label>
</HeaderTemplate>
<ItemTemplate>
TEXT
</ItemTemplate>
</asp:TemplateField>
</Columns>
</asp:GridView>
Or optionally you could just do this in GridViewRowCreated:
e.Row.Cells(0).Text = DataBinder.Eval(CType(sender.Parent, RepeaterItem).DataItem, "MyRepeaterDataItem")

Answer 2

Get Parent Data Item From Any Nested Control
After a little trial and error I worked out a simple solution that can work without any code behind.
VB.NET
<HeaderTemplate>
<%# DataBinder.Eval(Container, "NamingContainer.NamingContainer.DataItem.MyRepeaterDataItem")%>
</HeaderTemplate>
Where MyRepeaterDataItem is the data column.