Question

My content page

  <asp:updatePanel id="Panel1" runat="server" Visible="true">
         <ContentTemplate>
                <div>
                    blah blah
                </div>
          </ContentTemplate>
    </asp:updatePanel>

    <asp:updatePanel id="Panel2" runat="server" Visible="false">
         <ContentTemplate>
                <div>
                    yada yada
                </div>
          </ContentTemplate>
    </asp:updatePanel>     

Code file ..The following code is at the end of Submit button click event :-

            Panel1.Visible = false;
            Panel2.Visible = true;

Now earlier I was using asp:Panel..then it was working fine..like Panel 1 would hide and Panel 2 would show up instead..it was AFTER I changed asp:Panel to asp:updatePanel that things got screwed up…now the Submit button just won’t work !!

What’s gone wrong suddenly ?? I changed it to updatePanel so the page doesn’t refresh..isn’t this how we implement this thing ???

       <asp:updatePanel id="Panel1" runat="server">
          <ContentTemplate>
          <div>
     <p>
        Type ur name

                <asp:TextBox ID="name" runat="server">
                </asp:TextBox>
       </p>


        <asp:Button ID="btn" OnClick="btn_Click" runat="server" 
        Text="Submit" />
     </div>

    </ContentTemplate>
            </asp:updatePanel>


   <asp:updatePanel id="Panel2" runat="server" Visible="false">
    <ContentTemplate>
    <div>
       Thank You!

    </div>
    </ContentTemplate>
    </asp:updatePanel>

Answer 1

If you set Visible="false" on an UpdatePanel, it won’t be rendered to the client at all. Therefore, if you’re doing an Ajax postback, the client isn’t going to be able to make the invisible UpdatePanel visible, because it just isn’t there.

Think of UpdatePanels just as markers, showing which bits of your page you want to update on an Ajax postback. For your scenario, I think the easiest solution would be to use both UpdatePanels and Panels. Also, because the two things you’re updating (the two Panels) are right next to each other, there’s no need for two separate UpdatePanels:

<asp:updatePanel id="UpdatePanel1" runat="server">
  <ContentTemplate>
    <asp:Panel id="Panel1" Visible="true" runat="server">
      blah blah
    </asp:Panel>
    <asp:Panel id="Panel2" Visible="false" runat="server">
      yada yada
    </asp:Panel>
  </ContentTemplate>
</asp:updatePanel>

Then in the code-behind, change the Visible property on the Panel controls.