Asp.net Update Panel

Question

I am working in asp.net 3.5 and have some issue of update panel.I have some html content and Formview control in a page. I want to hide the html content when there is no data in the Formview and to show when there is data in the Formview control. My Formview control is in the updatepanel and it it is bind to SqlDataSource and Formview binds on some criteria. If somebody know how to solve this issue then please help me.

Thanks & Regards

Ashok

Answer 1

If you want the HTML content to be hidden after an Ajax postback, it will need to be in an UpdatePanel, either the same one your FormView is in, or a separate one.

If it's in a separate one, you'll need some way of forcing it to update when the FormView updates. You can either do this in some code-behind, calling the Update() method of the UpdatePanel, or by adding an AsyncPostBackTrigger to the UpdatePanel containing the HTML, maybe using the DataBound event of the FormView.

Also, to easily hide the HTML content, put it in a Panel, and use the Visible property.

An example of the trigger:

<asp:UpdatePanel ID="updatePanel" ... runat="server">
   <ContentTemplate>
      ...
   </ContentTemplate>
   <Triggers>
      <asp:AsyncPostBackTrigger ControlID="formViewId" EventName="DataBound" />
   </Triggers>
</asp:UpdatePanel>

Answer 2

This issue simply resolved using the putting all the html content in the Updatepanels and on UpdatePanel_preRender event of Updatepanels check that if Gridview has data then show html content otherwise hide