ASP.NET/AJAX - Web user control update panel triggering from outside

Question

I've got an web user control with an updatepanel. On my mainpage I got like 3 of those controls. Now I want to have an timer in the mainpage which would trigger the updatepanels in the web user controls.

How can I manage this?

Thanks in advance.

Answer 1

Using the AJAX Timer Control as an UpdatePanel Trigger

Implement an Update-Function in your UserControl which calls the Update-Function of their Update-Panels and call it from the Mainpage in the TimerTick-Event for every control. Set the UpdateMode of your UserControls's UpdatePanels=Conditional.

For example in your UserControl's Codebehind:

Public Sub Update()
    'bind Data to your UpdatePanel's content f.e.:
    Me.Label1.Text = Date.Now.ToLongTimeString
    Me.UpdatePanel1.Update()
End Sub

And in your Mainpage:

Private myControls As New List(Of WebUserControl1)

Private Sub Page_Init(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Init
     For i As Int32 = 1 To 10
        Dim newControl As WebUserControl1= DirectCast(LoadControl("./WebUserControl1.ascx"), WebUserControl1)
        myControls.Add(newControl)
        MainPanel.Controls.Add(newControl)
     Next
End Sub

Protected Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
    'in this example added dynamically
    For Each ctrl As WebUserControl1 In Me.myControls 
        ctrl.Update()
    Next
End Sub

In the UserControl's ascx-file:

<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
    <ContentTemplate>
        <asp:Label ID="Label1" runat="server" Text="Label"></asp:Label>             
    </ContentTemplate>
</asp:UpdatePanel>

In the Mainpage's aspx-file:

<asp:UpdatePanel ID="UpdatePanel1" runat="server">
    <ContentTemplate>
     <asp:Panel ID="MainPanel"  runat="server">
        <asp:Timer ID="Timer1" runat="server" Interval="1000"></asp:Timer>
     </asp:Panel>             
    </ContentTemplate>
</asp:UpdatePanel>