LinkButton in ListView in UpdatePanel causes full postback

Question

I have a LinkButton in a ListView in an UpdatePanel. I would like the button (well, any of them) to cause a partial postback, but they are causing a full page postback.

<asp:UpdatePanel ID="upOutcomes" UpdateMode="Conditional" runat="server">
  <ContentTemplate>
      <asp:ListView ID="lvTargets" runat="server" onitemdatabound="lvTargets_ItemDataBound">
        <ItemTemplate>
          <asp:LinkButton ID="lnkAddTarget" CssClass="lo" Text='<%# Eval("Title") + " <b>" + Eval("Level") + Eval("SubLevel") + "</b>" %>' runat="server"></asp:LinkButton>
        </ItemTemplate>
      </asp:ListView>
  </ContentTemplate>
</asp:UpdatePanel>

I found another post on stackoverflow which suggested adding this:

protected void lvTargets_ItemDataBound(object sender, ListViewItemEventArgs e) {
  var lb = e.Item.FindControl("lnkAddTarget") as LinkButton;
  tsm.RegisterAsyncPostBackControl(lb);  // ToolkitScriptManager
}

It hasn't made a difference...

There are a few other similar posts too, but I can't find a solution! Any ideas?

Solution 1

The ClientIDMode setting in ASP.NET 4 lets you specify how ASP.NET generates the id attribute for HTML elements.

In previous versions of ASP.NET (i.e. pre 4), the default behavior was equivalent to the AutoID setting of ClientIDMode. However, the default setting is now Predictable.

Read Microsoft Article

AutoId is required for this because of the way the script manager expects the HTML controls to be generated in previous versions of .NET.

Solution 2

I resolved this problem by setting: ClientIDMode="AutoID" on the page directive of the applicable page like so:

<%@ Page Title="" ClientIDMode="AutoID" Language="C#"%>

This is working fine.