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.
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>
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
Related
When an UpdatePanel Calls a method in server and for example this method change
textBox1.Text = "12312"
and this textBox1 was out of updatePanle scope
it dosn't change it text till a postback happend to the page
so I need after that calculation and chaging the Textbox's text in the server, I need to forcepage to do postback
plz can any one help ?
If you want to force a refresh you could try: Response.Redirect(Request.Url.AbsoluteUri)
This should force a redirect to the current page.
Hope this helps
If you wish for a control within the UpdatePanel to perform a standard postback, define a PostBackTrigger within the UpdatePanel, setting the ControlID to the ID of the control you wish to perform the postback.
<asp:UpdatePanel ...
...
<Triggers>
<asp:PostBackTrigger ControlID="ControlIDToPostBack" />
</Triggers>
</asp:UpdatePanel>
Or you could add the TextBox control you wish to update to another UpdatePanel setting both of the UpdatePanel's UpdateMode properties to Always.
This will ensure that the content within both UpdatePanel controls is updated for all postbacks that originate from the page. Which includes asynchronous postbacks.
<asp:UpdatePanel ... UpdateMode="Always"
I am developing my first asp.net website, my requirement is to refresh DropDownListB at SelectedIndexChanged event of DropDownListA, I have set AutoPostBack="True" for DropDownListA. Now the problem is whole web page gets refreshed, its unnecessary for me, is there any other technique that i can use to refresh only that control or only that panel rather than refreshing whole page?
Put the dropdowns inside
<asp:UpdatePanel ID="up1" runat="server">
<ContentTemplate>
// Dropdowns
</ContentTemplate>
</asp:UpdatePanel>
and include <asp:ScriptManager ID="sm" runat="server"></asp:ScriptManager> at the top
1- You can simply place the dropdown in an UpdatePanel, this will avoid a complete post back.
You can get more details on UpdatePanel here
2- You can use jQuery AJAX to fetch the data in JSON format and bind it to the dropdown list, this approach is more efficient but little complex in comparison to UpdatePanel
You can find so many articles on this if you search this on google , like
[EDIT]
You can find a similar implementation here
I am getting this error "An extender can't be in a different UpdatePanel than the control it extends". what could be the reason and how to tackle this problem.
You are using an AJAX ToolKit Extender Control to extend the functionality of one of your ASP.NET Controls. You have placed the Extender Control in a different UpdatePanel than the one the Extended Control resides in.
Both Extender and Extended controls must reside in the same UpdatePanel to avoid this exception.
Both Extender and Extended controls must reside in the same UpdatePanel to avoid the exception, this solved my problem.
I had an extra UpdatePanel that was giving this error, so I just had to remove the extra update panel lines of my aspx web page code.
What it says really - you've got an extender control that relates to a control that is in a different updatepanel. This means the extender is unable to act properly on the control it extends. You'll need to move your extender to be within the same updatepanel as the main control
In my case I was using button...outside the Update panel as below shown....
<asp:Button ID="btnClub" runat="server" Text="Club" OnClick="btnClub_Click" />
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
I just solved it by putting the <asp:Button ID="btnClub" runat="server" Text="Club" OnClick="btnClub_Click" /> inside the
update Panel
<asp:UpdatePanel ID="UpdatePanel1" runat="server">
<ContentTemplate>
<asp:Button ID="btnClub" runat="server" Text="Club" OnClick="btnClub_Click" />
Here you make your panel code
</ContentTemplate>
</asp:UpdatePanel>
Reason :Your iD is mis matching Ex:Text box id or dropdown id mismatch in Calender extender or RequiredFieldValidator
Ex:
Hear Id Value And Target Control Id Must Match .....
Check for controls with extenders that are have the same ID especially if you copy pasted from another form
Hi I got the solution of my problem by myself. The problem occurred when the target
control id of the extender control was different from the control it
had extend inside update panel. I resolved this proble a long time
back and replying now.
I'm trying to speed up my Repeater so that not as much HTML has to be resent via the AJAX UpdatePanel on each call.
So here's what I have (a very much simplified version):
<asp:Repeater ID="rptContactSteps" runat="server">
<ItemTemplate>
<p>Script:<br /><%#mobjSDIT.FormatText(Eval("script"))%></p>
<p>Notes:<br /><%#mobjSDIT.FormatText(Eval("notes"))%></p>
<asp:UpdatePanel ID="upStep" runat="server" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="rptContactSteps" EventName="ItemCommand" />
</Triggers>
<ContentTemplate>
<p>Contact/Step Notes:<br /><%#mobjSDIT.FormatText(Eval("contact_step_notes"))%></p>
<asp:ImageButton ID="btnSaveAndCompleteLastStep" runat="server" ImageUrl="~/images/content/buttons/save-and-complete-button.png" CommandArgument='<%#Eval("step_contact_tie_id")%>' />
</ContentTemplate>
</asp:UpdatePanel>
</ItemTemplate>
</asp:Repeater>
So, when I click 'btnSaveAndCompleteLastStep' I want all the UpdatePanel in 'rptContactSteps' to update. Having the UpdatePanel inside the ItemTemplate should help prevent having to re-load the html/text that populates the Eval("script") & Eval("notes"), since the value of these variables could be very large and over a 3G connection this could be very costly (in time & money).
I though by adding the async trigger it'd work as I have used this type of trigger before, but not when inside the Repeater. Currently the UpdatePanels aren't getting updated at all, except from the one from which the button was pressed.
Any ideas anyone?
They aren't getting updated except by the one that is called because the update mode is set to conditional, and by default the ChildrenAsTriggers is set to true. So if you want them all to update when one of them is changed, then you will need to find each of the update panels in each of the repeater items and call .Update() on the update panel, or you can change the update mode to "Always", or just wrap your repeater in an update panel instead of wrapping just the items.
Does that make sense? If not I can expand.
That behavior sounds ok to me because postback from within an updatepanel will not update anything outside of it by default.
One way you can try is on your btnSaveAndCompleteLastStep click , find each updatepanel in the repeater items and call Update() on it.
I have a page with two ContentPlaceHolders. One has a DropDown and another UpdatePanel with content.
How can I trigger update to the UpdatePanel by the DropDown's selectedItemChanged event when they are in different ContentPlaceholders?
The following would not work since UpdatePanel1 doesn't know about DropDown1:
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional" ChildrenAsTriggers="true">
<ContentTemplate>
Some content that needs to be updated here...
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="DropDown1" EventName="SelectedIndexChanged" />
</Triggers>
</asp:UpdatePanel>
One way is to make an ajax page method that would be called by javascript on the page when DropDown's item is selected. Then in code behind, inside that page method, call UpdatePanel1.Update().
Is there an easier alternative?
From http://msdn.microsoft.com/en-us/library/system.web.ui.asyncpostbacktrigger.aspx
The control that the
AsyncPostBackTrigger references must
be in the same naming container as
the update panel for which it is a
trigger. Triggers that are based on
controls in other naming containers
are not supported.
The workaround is to use the UniqueID of the control that the
trigger is referencing. Unfortunately the UniqueID isn't qualified
until the control has been added to its parent (and its parent
has been added to its parent, all the way up the control tree).
In your code behind, try:
UpdatePanel1.Triggers.Add(new AsyncPostBackTrigger()
{
ControlID = DropDown1.UniqueID,
EventName = "SelectedIndexChanged", // this may be optional
});
In the code-behind file, you should be able to do:
ScriptManager.RegisterAsyncPostBackControl(dropdown1);
You can enforce update any of page UpdatePanels by call updatePanel1.Update() method on server side.
For example during update updatePanel1 on button1.Click call updatePanel2.Update() and both panels will be updated.