Question

i have a gridview in updatePanel that i need to update every interval of time

what i have found so far on updating updatepanel is :

   <asp:UpdatePanel ID="UpdatePanel2" runat="server" OnLoad="Button1_Click">
        <ContentTemplate>
            <fieldset>
            <legend>UpdatePanel</legend>
            <asp:Label ID="Label2" runat="server" Text="Panel created.">
             </asp:Label>
            <asp:Button ID="Button1" runat="server"   
           OnClientClick="__doPostBack('UpdatePanel2', '');" Text="Button" />
            </fieldset>
        </ContentTemplate>
    </asp:UpdatePanel>

and this sub

  Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs)
    Label2.Text = "Refreshed at " & _
        DateTime.Now.ToString()
End Sub

though this works fine and update the panel but it postback the whole the page , you can tell when you see all the images reloading in another panel , i’m planning to update this panel every second

Question is How can i update UpdatePanel2 without affecting the other panel with the postback

EDIT

Another Question does any thing runs at the server side DO postback ?

Thanks

Answer 1

As of NET 3.5 there is the Web.UI.Timer control:

Performs asynchronous or synchronous Web page postbacks at a defined interval.

It is able to work with UpdatePanels, ensures that data (e.g. ViewState and updated control values) is not lost, and is “just another WebForm control”. However, the Timer must still cause a [partial] postback to go through the page life-cycle and rebind the grid again.

Depending on exact use-case, it may be better to use a true AJAX-approach to minimize the page life-cycle and data size overhead. (Telerik, DevExpress, and other 3rd-party libraries support “lightweight callbacks” for their Grid controls. Even more lightweight variants might include jqGrid.)