DataList child controls [resolved]

[blindlizard]

I have a DataGrid that I populate from a DataTable. In the FooterTemplate, I have 2 LinkButtons. How do I control the LinkButtons? When I try to access them directly like:

lnkbtnPrev.Visible = False

I get an error saying 'Object reference not set to an instance of an object' Now, I think I need to use the DataList's Controls collection, but I am unsure of how. I thought it would be"

dlstNews.Controls.Item(1).Visible = False

but that didn't do anything.

[nemaroller]

Datalist or datagrid? In reality I suppose it doesn't matter, they are both databound template controls.

There are a few ways you can accomplish this. You can change the visibility of the control inside the DataList_ItemDataBound routine...

Or you can access it directly in the Page_PreRender.

But considering once you bind the data, it doesn't change, there is no reason to have the framework parse code to change its visibility in the Page_PreRender event since the datalist is bound and knows what it is supposed to do thanks to viewstate.

see this thread for an example:

http://www.vbforums.com/showthread.p...hreadid=310220

[blindlizard]

Ok, I think that will do it, but what about if the button is in the footertemplate? Is it the same way?

[nemaroller]

The footer does not receive a DataItem, because its not bound to data. However, the datalist control still fires the _ITemDataBound event once for the header, and once for the footer. It just doesn't provide a datarecord to bind to (obviously).

So yes, you can use the DataBound event. You just check for
the footer itemtype (see code below)

Private Sub DataList1_ItemDataBound(ByVal sender As Object, ByVal e As System.Web.UI.WebControls.DataListItemEventArgs) _
Handles DataList1.ItemDataBound
       
        'remember, anything you want to access here on the
        'server-side (code-behind) must have included a runat=server tag
        'on the front-side (aspx html) page.
        '<FooterTemplate>
        '<asp:LinkButton ID="lb123" Runat="server"></asp:LinkButton>
        '<asp:LinkButton ID="lb124" Runat="server"></asp:LinkButton>
        '</FooterTemplate>
 
 
        [b]If e.Item.ItemType = ListItemType.Footer Then[/b]
 
            Dim l As LinkButton
            l = DirectCast(e.Item.Controls(1), LinkButton)
            l.CommandArgument = 3
            l.Text = "CANCEL"
 
            'now get 2nd linkbutton defined in the footer template
            l = DirectCast(e.Item.Controls(3), LinkButton)
            l.Text = "SUBMIT"
            l.CommandArgument = 5
 
        End If
    End Sub

[blindlizard]

Oh perfect, thanks!