Iam not sure if it has one.It might be a stupid question.
But I want to give Triggers like this in my dropdown's Update Panel
<Triggers>
<asp:AsyncPostBackTrigger ControlID="Control ID of Page" EventName="Load">
</Triggers>
Note: dropdown is Telerik Radcombox.
Can anyone tell me what to give in the Control ID part?
I'm not sure why you would use the Load event; events for triggers are client actions that trigger a server action, such as SelectedIndexChanged of a DropDownList when AutoPostBack="true" or Button Click event. Load happens during the natural postback and doesn't get triggered from the client. You can't specify the ClientID of the page for that reason. However, you could just use UpdateMode="Always" to always trigger asyncronous, or include more details of the problem.
Related
I am using an ASP.NET update panel to retrieve user info using the on TextChanged for the textbox, here is my code:
<asp:UpdatePanel runat="server" ID="up1" ChildrenAsTriggers="true">
<ContentTemplate>
<asp:TextBox runat="server" ID="loginEmail" Text="Email"
CssClass="textBoxes" OnTextChanged="userInfo" AutoPostBack="true"></asp:TextBox>
</ContentTemplate>
<Triggers>
<asp:AsyncPostBackTrigger ControlID="loginEmail" EventName="TextChanged" />
</Triggers>
</asp:UpdatePanel>
and the code behind:
string url, emailInfo;
emailInfo = loginEmail.Text;
url = Membership.GetUserNameByEmail(emailInfo);
emailText.InnerText = "Email: " + emailInfo;
urlText.InnerText = "Webiste: http://www.Elwazefa.com/User/" + url ;
the code wont fire on textchanged but it wil,
on ButtonClick or PageLoad.
What is the problem?
Using ASP.NET 4.0
<asp:TextBox AutoPostBack="true" OnTextChanged="thingId_TextChanged" ID="thingId" runat="server"></asp:TextBox>
AutoPostBack on text-box will trigger post-back when the focus is lost from the text box. TextChanged event will be fired on any subsequent post-back (can be due to button-click or text box focus change). So you need to make certain
After text is changed, you are moving out of text-box
Whatever controls that you are change are part of update-panel (can be different update panel). If there are not part of any update panel then those changes won't get reflected on client side.
My guess is you are probably suffering from #2. You can use tool such as Fiddler (or Firebug on FireFox) to check if browser is firing AJAX (XHR) request when the focus is lost from the text-box.
As #VinayC posted, AutoPostBack means that the page will postback to the server when your TextBox loses focus. No built-in event causes postback on every character added to a text input, and for good reason. UpdatePanel postbacks don't cause the page to flicker, but they can be just as heavy as a full postback.
If you want to work around this, you can give your textbox a client onchanged event handler, the JavaScript of which will be built from Page.ClientScript.GetPostBackEventReference().
The correct solution would be to use an AJAX method call from your JavaScript code rather than an UpdatePanel partial postback in onchanged.
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 have made a ToolBar usercontrol in a update panel. All buttons should work client side except a print button. I want to make this use the original postback.
ScriptManager.GetCurrent(Me).RegisterAsyncPostBackControl(Toolbar2.PrintButton)
However the button still doesn't refresh the page...
Any ideas?
You must set AutoPostBack to true? of the PrintButton that you have created
Rather than using the script manager to register a control as asynchronous, instead set the button as a trigger on the update panel itself, which you also can do via code.
HTH.
When you use RegisterAsyncPostBackControl you must also manually refresh the update panel using the Update() method.
http://geekswithblogs.net/lszk/archive/2011/08/08/playing-with-update-panels.aspx
You can use the Triggers property of the UpdatePanel to register actions that trigger a full postback.
Add a PostBackTrigger object to that property, containig the ControlID of the control which needs to trigger a full postback.
<asp:UpdatePanel ID="UpdatePanel1" UpdateMode="Conditional" runat="server">
<ContentTemplate>
...
</ContentTemplate>
<Triggers>
<asp:PostBackTrigger ControlID="myFullPostBackControlID" />
</Triggers>
</asp:UpdatePanel>
I am completely stumped on this and would really appreciate any help.
I am working on a user control that is situated inside of an update panel. There is a button on the form which loads some data. This is working correctly.
There is also a drop-down box to filter the data. Changing this does initiate a post back, however nothing happens. The drop-down box goes back to it's default value the OnSelectedIndexChanged function is never called.
I've put break points in page_prerender and page_preload and both are being hit the post back is definitely occuring. Breakpoints withing the dropdownGroup_changed function are never hit.
Removing the update panel solves the problem, however it breaks the rest of the page so I can't use that for anything other than testing.
I've also verified that there is nothing in my prerender / page load that is resetting the page's state.
Here is the update panel code:
<asp:UpdatePanel ID="UpdatePanel6" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional" >
<ContentTemplate>
<ucControlName:ControlName ID="ControlName1" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Here is the drop-down in question - It is located inside of the user control
<asp:DropDownList ID="dropdownGroup" runat="server" Visible="false" AutoPostBack="true" OnSelectedIndexChanged="dropdownGroup_changed"></asp:DropDownList>
It is of course visible and databound by the point in the code where the issue is occuring
A bit more info-
added Both a hard coded dropdown (To rule out a stupid databinding issue) and a textbox to the same control. I have the same issue.
It appears that the event isn't triggering because the values are never changing as far as .net is concerned. I've checked the control during page_init and page_load - the value is always the same.
The fact that the button works but the other controls don't makes me think that there is a view state issue here somewhere but I can't quite ferret out what is causing it. Viewstate is enabled for the page and the panel- don't know if anything else could be overriding / corrupting it.
Did i mention that I hate update panels with a passion? because I hate update panels with a passion.
I suggest checking the 'Value' property for each 'ListItem' in the 'DropDownList' control. If they are all the same even if the 'Text' properties are different, then the 'OnSelectedIndexChanged' will not fire at all since ASP.NET cannot tell if anything has changed (See this related question for more info.)
This was the real cause of my problem even though I, too, had a 'UserControl' with a 'DropDownList' inside an 'UpdatePanel' and the 'AutoPostBack' was firing as expected. I thought the UpdatePanel was the culprit but it was not the case. Each of the items in my DropDownList had the same underlying value of "10" even though they had distinct 'Text' values. I changed them to each have a unique value which then allowed for the OnSelectedIndexChanged event to fire thus fixing the problem.
Two answers for the price of one:
Are you calling DataBind() in your Page_Load? If you do that on a PostBack, you will lose events. Replace the call with the following:
if (!IsPostBack) {
DataBind();
}
If your DropDownList is outside your UpdatePanel, you need to add a Trigger as follows:
<asp:UpdatePanel ID="UpdatePanel6" runat="server" ChildrenAsTriggers="true" UpdateMode="Conditional" >
<Triggers>
<asp:AsyncPostBackTrigger ControlID="dropdownGroup" EventName="SelectedIndexChanged" />
</Triggers>
<ContentTemplate>
<ucControlName:ControlName ID="ControlName1" runat="server" />
</ContentTemplate>
</asp:UpdatePanel>
Have you tried UpdatePanel.Update (); after your databind.
We have an issue on our page whereby the first time a button posts back (we have ASP.NET ajax to enable partial updates) nothing happens, then on every subsequent click, the information is updated as if the previous event fired.
Here's the code for the page. The events are button clicks fired from within the table. Which is rerendered at the backend.
<asp:ScriptManager EnablePartialRendering="true" ID="scrptMgr1" runat="server">
</asp:ScriptManager>
<asp:UpdatePanel runat="server" ID="folderContainer">
<ContentTemplate>
<asp:Table id="FolderTable" CssClass="FolderTable" runat="server" CellSpacing="0"></asp:Table>
</ContentTemplate>
</asp:UpdatePanel>
Any ideas?
Thanks.
Did you try an HTML table, with or without runat="server" ?
Do you add or remove controls inside the table in the postback?
Inspired by Robert's answer:
In which event handler do you build your table? If you build it in Page_Load without checking IsPostBack), then the button's click event has not been handled yet.
You need to build the table in the button click handler.
Your table is probably being populated too late in the page lifecycle. Try creating the table in PreInit.