I have a page and it has a button and a user control.
I want to refresh the user control without refreshing the page.
I know I cannot do it otherwise so what I did is wrapped my user control inside the Update Panel.
<asp:TextBox ID="txtName" runat="server"></asp:TextBox><br />
<asp:Button ID="btnAdd" runat="server" Text="Add name to list" OnClick="btnAdd_Click" /><br /><br />
<asp:UpdatePanel ID="upShowNames" runat="server">
<ContentTemplate>
<uc1:ShowNames ID="ucShowNames" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnAdd" />
</Triggers>
</asp:UpdatePanel>
But I still the control won't refresh.
I also tried calling the update panels. The Update() method by changing its UpdateMode to Conditional but that does not work either...
Does anyone know how can I do it?
Please change these 2 things
<asp:UpdatePanel ID="upShowNames" runat="server" UpdateMode="Conditional">
<asp:AsyncPostBackTrigger ControlID="btnAdd" EventName="Click"/>
You missed the EventName on the postback trigger, once you add that, it should work :-)
Related
Consider the following code fragment:
<div>
<asp:Button runat="server" ID="trickyUPTrigger" Text="Tricky Update" />
<div>
<asp:Button runat="server" ID="normalUPTrigger" OnClick="normalUPTrigger_Click" Text="Normal Update" />
<asp:UpdatePanel runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="normalUPTrigger" />
</Triggers>
<ContentTemplate>
<asp:Label runat="server" ID="changeableLabel" Text="Change me"></asp:Label>
</ContentTemplate>
</asp:UpdatePanel>
</div>
</div>
Now make the button with ID of trickyUPTrigger as the trigger of the UpdatePanel. Or, devise a mechanism (probably... using javascript?) so that when this button is clicked UpdatePanel updates without full page postback.
If you want to update the UpdatePanel when clicking on trickyUPTrigger, you can add that button to the triggers list:
<asp:UpdatePanel runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="normalUPTrigger" EventName="Click" />
<asp:AsyncPostBackTrigger ControlID="trickyUPTrigger" EventName="Click" />
</Triggers>
<ContentTemplate>
...
</ContentTemplate>
</asp:UpdatePanel>
UPDATE
You asked some code examples showing cases with naming containers, a concept that comes into play for databound controls with item templates, like the GridView and the ListView, and for user controls. In the examples below, I use a ListView, where each item is a separate naming container.
If you wanted to trigger an update of your panel from a button in a ListView item template, the trigger would not be found at runtime, and an exception would occur:
<asp:ListView ID="lstView" runat="server">
<ItemTemplate>
<asp:Button ID="anotherTrigger" runat="server" Text="This trigger cannot be found!" OnClick="anotherTrigger_Click" />
</ItemTemplate>
</asp:ListView>
<asp:UpdatePanel runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="anotherTrigger" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
The reverse case (the UpdatePanel in the ListView item template, the trigger button outside of the ListView) does work, according to my tests, which seems to contradict the note that you mention in your comment:
<asp:ListView ID="lstView" runat="server">
<ItemTemplate>
<asp:UpdatePanel runat="server">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="anotherTrigger" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
</ItemTemplate>
</asp:ListView>
<asp:Button ID="anotherTrigger" runat="server" Text="This trigger works!" OnClick="anotherTrigger_Click" />
Finally, the case where the UpdatePanel and the trigger button are both in the ListView item template also works:
<asp:ListView ID="lstView" runat="server">
<ItemTemplate>
<asp:Button ID="anotherTrigger" runat="server" Text="This trigger works!" OnClick="anotherTrigger_Click" />
<asp:UpdatePanel runat="server" UpdateMode="Conditional">
<Triggers>
<asp:AsyncPostBackTrigger ControlID="anotherTrigger" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
</ItemTemplate>
</asp:ListView>
You can notice that I set UpdateMode="Conditional" for the panel in this last example. With this setting, the panel is updated only by its own triggers. If the attribute is set to UpdateMode="Always", the panel is updated not only by his own triggers but also by the triggers of the other UpdatePanels in the page. The default value is UpdateMode="Always" (as in your code sample).
I have an obout ColorPickerExtender in an UpdatePanel along with some other controls. The other controls execute partial postbacks as expected, but the ColorPickerExtender executes a full postback despite being in the UpdatePanel. Here's the relevant ASPX:
<asp:Content ContentPlaceHolderID="cphMainDivContentPlaceHolder" runat="server">
<asp:UpdatePanel ID="upGeneralLayoutData" runat="server">
<ContentTemplate>
<asp:TextBox ID="txtLayoutName" runat="server"
ToolTip="Enter a name for this layout (recommend you use a unique name)"
OnTextChanged="txtLayoutName_TextChanged"
AutoPostBack="true"
MaxLength="255" />
<obout:ColorPickerExtender ID="cpeLayoutBackgroundColor" runat="server"
OnClientOpen="onColorPickerExtenderOpen"
AutoPostBack="true"
TargetProperty="style.backgroundColor"
OnColorPostBack="cpeLayoutBackgroundColor_ColorPostBack"
PopupButtonID="txtLayoutBackgroundColor"
TargetControlID="txtLayoutBackgroundColor"
HexView="False"
PickButton="False" />
<asp:TextBox ID="txtLayoutBackgroundColor" runat="server"
ToolTip="Select the background color for this layout"
CssClass="ColorPickerExtenderTextBox"
style="cursor: pointer"
Width="50"
ReadOnly="True" />
<br />
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
As I was formulating the question, I was able to figure out the answer (see below)--instead of trashing the question, I left it here for others to use.
It turns out that the ColorPickerExtender is not being registered as an async postback control. I got the clue from this post. I'm not sure why it doesn't register as an async control when the others do, but the fix is easy enough--add a <Triggers> section that explicitly designates it as async, like so:
<Triggers>
<asp:AsyncPostBackTrigger ControlID="cpeLayoutBackgroundColor" EventName="ColorPostBack" />
</Triggers>
I want to reload the image on a button click without refreshing the page. For now, the image is changing when i click on "Refresh Image" link button. But the PAGE REFRESHES..
Code :
<asp:UpdatePanel ID="UpdatePanel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="txtCaptchaInput" BorderStyle="Solid" Style="vertical-align: top" runat="server" Width="106px" BorderWidth="1px"></asp:TextBox>
<asp:Image ID="img_captcha" runat="server" Height="32px" ImageUrl="~/captchaJPEG.aspx" Width="108px" />
<asp:LinkButton ID="captcha_refresh" runat="server">Refresh Image</asp:LinkButton>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="captcha_refresh" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
What am i doing wrong with this code ? I am using asncpostbacktrigger and assigning a control id and event name to it. Which to my knowledge is a correct approach. Please advice.
Remove Triggers from UpdatePanel1, Add Click event handler to captcha_refresh Link button. Inside that event call UpdatePanel1.Update();
Im trying tp upload more than one image, and when each one I upload I will show it in a repeater, but in the code behind the FileUpload1.HasFile is always False , this is a piece of my code :
<asp:UpdatePanel ID="UpdatePanel1" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional" >
<ContentTemplate>
<asp:Repeater ID="rpUploadedImages" runat="server">
<ItemTemplate>
<img src='../Images/<%# DataBinder.Eval(Container.DataItem, "ImagePath")%>'/><br />
</ItemTemplate>
</asp:Repeater>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="btnupload" EventName="click" />
</Triggers>
</asp:UpdatePanel>
<asp:FileUpload ID="FileUpload1" runat="server" /><br />
<asp:Button ID="btnupload" runat="server" Text="Upload" onclick="btnupload_Click" />
The FileUpload control does not work with UpdatePanel, you will need to do a full post back to get the file on the server... Now there are a lot of tricks to make it ajaxy...
http://geekswithblogs.net/ranganh/archive/2008/04/01/file-upload-in-updatepanel-asp.net-ajax.aspx
Another tricky way is to create iframe with fileupload + submit button(or some trigger) inside your main form. iframe will postback with no effect to main page.
I have a page with some UpdatePanels, each one with its own button to update it. Since the update routines can take some time, I thought making them Asynchronous would help loading the page step by step.
But doing so, when I fire programatically the update routine of each panel, I get only the last UpdatePanel updated.
Here is an example of the code, with two UpdatePanels. There is the requirement that the update routine have to be fired on clientside pageLoad function.
Is it a bug or am I missing something in the code?
Thanks =)
<asp:UpdatePanel ID="Panel1" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="Text1" runat="server" />
<asp:Button ID="Button1" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button1" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
<asp:UpdatePanel ID="Panel2" runat="server" UpdateMode="Conditional">
<ContentTemplate>
<asp:TextBox ID="Text2" runat="server" />
<asp:Button ID="Button2" runat="server" />
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Button2" EventName="Click" />
</Triggers>
</asp:UpdatePanel>
And the client-side code:
function pageLoad()
{
$('#Button1').click();
$('#Button2').click();
}
Here is why:
By default, when a page makes multiple
asynchronous postbacks at the same
time, the postback made most recently
takes precedence.
http://www.asp.net/ajax/documentation/live/tutorials/ExclusiveAsyncPostback.aspx
Here is a solution:
Handling Multiple Asynchronous Postbacks