server side function is not fired while post back in jquery ui - asp.net

There is a drop down list in the jquery ui modal form with id - drpAction.When the selection is changed I need to execute drpAction_SelectedIndexChanged function in the code behind. When I just try to invoke the function like onSelectedImdexChanged="drpAction_SelectedIndexChanged" ,the function is not fired.
How can I solve the problem?

Do you want a full postback, or an AJAX call? For full postback, add AutoPostBack="True" to your DropDownList. For an AJAX call, you should hook a JQuery event handler to the DropDownLists "onchange" event (remember that a DropDownlist is rendered as a SELECT tag)

Related

AJAX Add a dynamic form and AJAX Post data

This is what I'm trying to do with AJAX:
[DropDownList]
I have a DropDownList (not inside an UpdatePanel), populated by different Products to "Add" to the database.
[UpdatePanel #1]
Below, I have an Conditional UpdatePanel that listens for "SelectedIndexChanged" on the DropDownList, when that event is triggered it adds TextBoxes to a div "productForm" inside the UpdatePanel. It creates the Form according to the Product to add.
[Button]
Below the UpdatePanel I have a button that "should" submit the form above.
[UpdatePanel #2]
I have an update panel that listens for the event on Button "Click" event. I also have a div in the ContentTemplate that should post out data that was submitted from the "Add Product Form" in the first UpdatePanel.
The thing is, when I submit (and the Controls are still visible in the first UpdatePanel. It can't read the data from the TextBoxes becaus they aren't there. Also, if I try to add all this to the same UpdatePanel, the Controls disappear whenever I click the Submit button.
Any ideas how to make something similar work?
Without the code I can suspect that when you dynamically populate first div on dropdown selected index changed event, since its within update panel, viewstate is never made aware of new controls and on submit can't post them back to server.
I've had some bad experiences with update panel and never use it other than very simple scenarios. Try getting familiar with jQuery ajax. I would do what you want to do using jQuery and web methods.

TextBox keydown event at server side in asp.net

i have a textbox on a page, now whenever any age number is entered in that page, that page should be loaded in my datalist, i have created rest of the thing, but i am not getting how to trigger the textbox onkeydown event from asp.net, i know working with that from javascript, but the problem is i have below things done in that function:
it applies the currentpage value to the static variable from textbox
it binds the datalist
it enable disable the next previous buttons accordingly
and i dont think this i can do from javascript, anyone have any resolution, how this could be achieved from server side, onkeydown event
You can capture the keydown event in a javascript function then do a AJAX call to the server. If this does not suit you, then you could try manually do postback in javascript.
So in your textbox:
mytextBox.Attributes.Add("onkeydown", "return doDataListBind()");
Now in the javascript function:
function doDataListBind()
{
__doPostBack("myTextBox"); // etc, etc
// some other code here...
}
More info can be found here:
http://geekswithblogs.net/mnf/archive/2005/11/04/59081.aspx
http://www.asp.net/ajaxlibrary/AjaxControlToolkitSampleSite/
Try looking into or using either:
AJAX Control Toolkit, or
JQuery Autocomplete Plugin
Alternatively you could try to call _postback() function from a client side event/function for your textbox in javascript

ASP.NET button click fire jQuery

I have a jQuery Pager control, for each page there is a set of textboxes and a submit button. When this submit button is clicked I want it to fire off some jQuery to update the controls on the front end (i.e. current page, set visibility of controls etc). The button is an asp.net web forms postback button.
Does anyone know any way of doing this?
Merry Christmas!
Inject js from code-behind after your postback success like:
string script = "$(function(){setPage(\"" + yourpagenumber+ "\");});";
ScriptManager.RegisterStartupScript(this.Page, this.Page.GetType(), "Pager", script, true);
And in the js you will have a setPage function that does the job of setting page with your jquery pager plugin.
function setPage(pagenumber){
alert(pagenumber);
//do your page setting here
}
Note: you can use Page.ClientScript.RegisterStartupScript if that fits your needs but the idea remains same.
Don't use a submit button, use an input of type button with an onclick event instead.
Use the OnClientClick attribute of the asp:button i.e.
OnClientClick="JQueryFunction();return false;"
for no postback and
OnClientClick="JQueryFunction();return true;"
for a postback. I'm assuming that that JQueryFunction() returns true.

Use asp.net AJAX from javascript

This is probably a simple question.
I use ASP.NET ajax toolkit and Jquery. I want to call a server-side function/method from Javascript and have it update a control. Can i do this?
Client-side
send_request(foobar,args);
Server-side
private void foorbar(){
Label1.Text = "updated";
}
Do you want it to fire a server-side method and update a server-side control on the page? You can create a ASP.NET UpdatePanel, let's say there is a button1 inside, and from your JQuery code, write this.
function OnClick()
{
__doPostBack(button1.ClientID, "argument")
}
and in your server side code, Page_Load event, you will find the EVENTTARGET and EVENTARGUMENT in the REQUEST variable, which contains the information you just postback, you can then update the control in the UpdatePanel itself as long as the control is within the UpdatePanel, it will be handled properly by ASP.NET AJAX.
More details here
http://www.dotnetspider.com/resources/16920-Post-back-gets-demystified-doPostBack-defined.aspx
Yes that can be done Client Callback
You could take a look at ASP.NET Page Methods.
jQuery.ajax({
url:'url to call', //usually webservices in asp.net
dataType:'json',
type:'POST', //(asp.net werbservices by default accepts POST request only)
success:function(data){
//do some thing with this data, like will dom elements etc
}
});
#smkngspcmn:
I placed everything inside an update panel and did something like $('#Year').change(function() { __doPostBack("submit", ""); }); That does do a full post back without Ajax. What am i doing wrong? Should i place the above script inside the update panel as well?
The first argument to __doPostBack() should be the UniqueID of a server-side control inside the UpdatePanel. For example, you can put a hidden button inside the UpdatePanel:
<asp:Button ID="HiddenButton" runat="server"
style="display:none" OnClick="HiddenButton_Click" />
When the button is rendered on the page, you can take the name attribute of the <input type="submit"> element that represents the submit button and use it for the first argument to _doPostBack(). In this way, whenever your script runs it the UpdatePanel will make an asynchronous postback and the HiddenButton_Click event handler will be fired.

Controls in UpdatePanel losing JQuery Events

I have a button that is within an updatepanel control. The button's click event has a function defined for it through JQuery. Once the async postback completes the JQuery event fails to fire when the button is clicked subsequently. What do I need to do to correct this behavior and maintain the JQuery event attachment to the button's click event once it has been refreshed asynchronously?
put your jquery event handler binding inside the following function
function pageLoad(sender,args) {
// binding code here, for example
$('#button').click(function(e) {
// do something when the click event is raised
});
}
pageLoad is executed after every postback, synchronous or asynchronous. pageLoad is a reserved function name in ASP.NET AJAX that is for this purpose. $(document).ready() on the other hand, is executed only once, when the DOM is initially ready/loaded.
See this Overview of ASP.NET AJAX client lifecycle events

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