Question

I have some sort of a strange problem, I have an update panel which is triggerd by a timer.

Also I have on this page is a function that calls the DB and retrieves data from it. the function does not being called from the update panel or even related to it.

the problem is that I see in my log file that every time there is a tick and the update panel being updated there is also a call to my DB server (this function is in the page_Load section ) to retrieve the data again. but the page doesn’t seem to do a full postback (It stays the same and doesn’t looks like being reloaded)

my code:

<asp:Timer runat="server" id="UpdateTimer" interval="5000" ontick="UpdateTimer_Tick" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
    <Triggers>
        <asp:AsyncPostBackTrigger controlid="UpdateTimer" eventname="Tick" />
    </Triggers>
    <ContentTemplate>
        <span id="s1" runat="server"></span>
    </ContentTemplate>
</asp:UpdatePanel>  

and code behind:

protected void UpdateTimer_Tick(object sender, EventArgs e)
{
    DateTime dt = TimeConvertor.getCurrentGameTime();
    s1.InnerText = String.Format("Current game time: {0:dd/MM/yyyy HH:mm}", dt);
}

The function to retrieve data from the DB is in the page_load of the page.

Any help is appreciated

Thank you

Doron

Answer 1

Using the Update panel doesn’t refresh whole page, only controls inside update panel, but when Partial Update is executed all the server page life-cycle events occur, and view-state and form data are preserved, but when rendering page only part of update panel is rendered and returned to user.

Go to this link Partial page rendering

and scroll to the section background.