Forms Data Controls :: How To Execute Asynchronous Event
Jan 5, 2011
I am having a gridview in which there are many columns. The Last column is button column with command name as Select.
In row command event, I am creating a webreqest instance and passing the url of the required page in my application, and based on the response status code, updating the column value for that particular row.
This is working.
What I want is this should be asynchronous. Means, if I click the first row Select button, then it should fire and process request. Meanwhile I should be able to click other row's Select button, even if the previous button's click event is still in process.
Means the communication should be asynchronous. Even if
I've got a user control with a couple of buttons. Think of them as 'On' and 'Off'. When either button is clicked an async method is called. If the method is successful an event is fired. Within the event I want to update the enabled property of the two buttons so that only a single button is clickable at any one time. The problem is that any changes I make to the properties are not shown on screen because the postback is already complete. I tried wrapping the buttons in an UpdatePanel but I get an "Update method can only be called on UpdatePanel with ID 'xxxx' before Render' error. I understand why the problem occurs but I can't think of a solution.
Ideally what I'd like to do is simply call a method within the event that will update the UI, but I don't know if that's possible.
EDIT
Here's some example code. I can't post the exact code, but this explains the problem:
I have a scenario where I have two data grids (both dynamic) to be loaded onto a page. However, the data that needs to be shown on one of the grids has no dependence on the data of the other grid. So, when fetching the data, I want to fetch it in an asynchronous manner and bind that data to each of the grids individually. Currently we have a code like
GetData(ForGridOne) ; GetData(ForGridTwo);
I want to make these calls asynchronously so that in order to load the page, the time taken would be lesser. What should be the ideal way to go forward with this ? One more thing, we would be hosting the application in a portlet which doesn't support AJAX.
I have a page that is using the Ajax asynch file uploader. What I would like to have happen is after the file is uploaded I would like to have it displayed in a list on the page. I am looking for a way to fire a callback event when the file upload is complete. Is it possible using the asynch fileupload control?
Now imagine that you're writing an ASP.NET app and you've generated a proxy for the service with the async operations. You create an instance of the service, wire service.GetCustomerCompleted to your handler, OnGetCustomerCompleted, and call service.GetCustomerAsync("12345"). In OnGetCustomerCompleted you apply logic to detect that no customer was found and throw a custom exception, or you want to throw the exception found in e.Error, e.g.:
void OnGetCustomerCompleted(object sender, GetCustomerCompletedEventArgs e) { if (e.Error != null) throw new ApplicationException("GetCustomer failed", e.Error); if (String.IsNullOrEmpty(e.Result.FirstName) && String.IsNullOrEmpty(e.Result.LastName)) throw new CustomerNotFoundException(); }
(I've omitted the bits of code that sets up a Customer object and persists it through the calls.) You launch the call to GetCustomerAsync in Page_Load and expect to retrieve the result in a handler wired to Page.OnPreRenderComplete. My question is, how do you catch the exception in your page? I know you can catch it with Global.asax's ApplicationError, but what if you don't want to navigate away from your page?
I have Website Application , in which i have method ..i want to execute this after every 10 days automaticlally ..what is the concept of doing this , provice some code etc. if possible ..
I'm going nuts here.. This is what i like to do: When i click my serverbutton i want a fade message to show and then execute as usual all the servercode (db insert and more) i have in my button_click event in code behind. The fade effect works, but the servercode never executes. I don't know how many guides i have tried but it seems impossible to achieve this. I just want to fire the the code in my click_event. I really hope someone of you can point me in the right direction.
I thought that Page_Load events executed every time a page was loaded not just the first time. Am I wrong on this?
I have a Page_Load event that writes text to a label to display on the screen:
Output.Text &= "Welcome to my Website <br />" (Output being the ID of a Label control)
I also have an On_Click event for a button to display the same information:
Output.Text &= "Welcome to my Website <br />"
After clicking the button, I expected to see the output twice. Once for the page being reloaded and once for the click event. I thought that Page_Load events executed every time a page was loaded not just the first time.
have a gridview which has a delete linkbutton in 1 column, problem is that the click event for the button is not firing at all, the page does postback but the breakpoint wont execute and jump in the click event at all.
in my asp.net website, i have textbox control inside datagrid control. I would like to add textchange event in javascript where i need to sum the values inside textboxes in datagrid and show that addition in lable outside grid. I would also like to do same addition in codebehind(*.cs) But codebehind only execute when browser not support javascript. It means when browser support javascript only client side javascript should execute not server side code
I have a textbox in my app in which I have code behind in the "onTextChanged" event that I'd like to execute without doing an entire page post back .
I can't use use AJAX not an option for me (corporate thing).
Anyways, I have been struggling with the specifics on implementing ICallbackEventHandler. Or is than another way I can/should do this.The code in the textChanged event pulls a dataset from the DB and does a validation.
How can I trigger a jQuery function with the Gridview Select button? I want that the select button trigger the jquery function that has the row details (it's already working with a asp:buttonfield ), and select the row so i can get the values and send it trough e-mail with another button. I don't know if this is possible. or, Can I trigger the jQuery function from code behind with the select button Sub? How?
[Code]....
This function capture the gridview cell values that are hidden and show them in a div outside the gridview (it works as row details). I have no problem with this.
[Code]....
All i need is a button that select the row index and/or values and trigger the jquery function . Or I can execute the jQuery function from server side. I don't know if it's posible.
I tryed to put a nested Gridviews (parent-child) in an UpdatePanel, but it didn 't work as I want. Firstly the code of the Gridview (its from the example reffering to this [URL] .....)
why the gridview RowDataBound event fires during a select command. I only expect it to run when the gridview is being populated with data. Is there some way to stop it from running when the select command is triggered?
I have one Datagrid with Footer. Footer Row Contains Input fields with one Button to add New Values. I have button click event but not getting fires. my code follows:
I am facing one strange problem,I have a gridview in which the last two columns have checkboxes and on those checkboxes click event I am doing some database operations.I also have one checkbox that is outside the gridview which actually shows or hides some of the gidview columns.This was all working well but now I have shifted that grid to a user control because I have to use it in two pages.The problem now is,When the page first loads and I click the check box or any control in the page that is outside the grid then it works perfectly.But once I click any of the check box within grid view column then its behavior chages, now even if I click the checkbox that is outside the grid then also the checkbox_CheckedChanged event of the checkbox that is whithin gridview is fired.That checkbox event then behaves something like a page_load event that is called for every page load and for every event with in the page after it is called once.
I have 3 user controls that I have to load at the same time. They each contain a gridview that pulls data from the database. They are doing a "delay" load of the data so there is a progress bar template that shows that the data is loading however the first gridview fires and loads, then the second, then the third and I need them to all fire at the same time.
I am generating an html flow into Update Panels in a content ASPX page (VB.Net 2008 Professional w/ SP1). These include EDIT anchor tags that call a javascript function which calls __doPostBack(target, args); so I can interact with the code behind. This all works fine except on some of the postbacks the connection with the browser just seems to get closed prematurely and suddenly the webpage displays a directory listing. When debugging it, it only happens sometimes, at different places for the E and D options below but not for the V or AddPost or AddArticle. I am just stepping through E or D and suddenly the web page show a directory listing. (What is that? Is the connection crashing? Is the page suddenly redirecting to the base directory because it crashed?)
