Nested Datalists down to GreatGrandChild level

Question

I've been "successful" at getting nested datalists to work through four generations (Parent, Child, GrandChild, GreatGrandChild) but only with recordsets less than 50 and almost a minute of churn time. Now that I've got about 500 records, the request is timing out.

I've tried several methods I've found online for successfully getting Parent-Child datalists but I couldn't get recursing to work through to GrandChild without an error for using too many Open Connections.

Could anyone share a best practice for a speedy, four-generation nested datalist?

Here is the example code behind for databinding the Child and GrandChild datalists:

Sub Item_Bound_Child(sender As Object, e As DataListItemEventArgs)

    If e.Item.ItemType = ListItemType.Item Or _
        e.Item.ItemType = ListItemType.AlternatingItem Then

        ' Retrieve the Label control in the current DataListItem.
        Dim Parent_Name_Label As Label = _
            CType(e.Item.FindControl("lbl_Parent_Name"), Label)

        Dim s As SqlDataSource = DirectCast(e.Item.FindControl("DataSource_Child_Data"), SqlDataSource)

        s.FilterParameters(0).DefaultValue = Parent_Name_Label.Text
        s.DataBind()


    End If

End Sub
Sub Item_Bound_GrandChild(sender As Object, e As DataListItemEventArgs)

    If e.Item.ItemType = ListItemType.Item Or _
        e.Item.ItemType = ListItemType.AlternatingItem Then

        ' Retrieve the Label control in the current DataListItem.
        Dim Parent_Name_Child_Level_Label As Label = _
            CType(e.Item.FindControl("lbl_Parent_Name_Child_Level"), Label)
        Dim Child_Name_Label As Label = _
            CType(e.Item.FindControl("lbl_Child_Name"), Label)

        Dim s As SqlDataSource = DirectCast(e.Item.FindControl("DataSource_GrandChild_Data"), SqlDataSource)

        s.FilterParameters(0).DefaultValue = Parent_Name_Child_Level_Label .Text
        s.FilterParameters(1).DefaultValue = Child_Name_Label .Text
        s.DataBind()

    End If

End Sub

I can only imagine that I'm leaking something somewhere or doing too many round-trips. I sure would appreciate some direction and help.

Thanks, Rob

Answer 1

I found this explanation to be very helpful to set up databinding for multiple-level nested datalists. While the code was initially very intimidating, I learned it and adapted it to my use.

http://msdn.microsoft.com/en-us/library/aa478959.aspx

Now my nested datalists display in a matter of seconds.

My next step is to learn how to edit the GreatGrandChild datalist in place.