This is perhaps related to this question, but I have slightly more information.
I recently updated an ASP.Net application to .NET 3.5 after coding a few new pieces with Linq. Now my pages intermittently stop firing event handlers. I have it narrowed down to pages with Ajax on them, and I assume it's either the ScriptManager or the AjaxControlToolkit registration that is precipitating the problem.
The really screwy part is that pages seem to work fine about 2/3s of the time, and the controls lose their event handlers only 1/3 of the time. I wondered about some type of error occurring and the page not rendering correctly, but I cannot find evidence of this.
We were have exactly this issue and as you have said it was only happening some of the time and only on pages with Ajax requests. We found that disabling the HTTP Keep-Alive as suggested in the answer to
Why does Internet Explorer not send HTTP post body on Ajax call after failure? worked.
This can be done in IIS7 by following the instructions in How to configure HTTP KEEP-ALIVE in IIS 7
i have only used Telerik Ajax controls so far, and my observation is if an exception occours in a Ajax enabled control, nothing happens. No exception report, no action. nothing.
Maybe you should test you app without ajax to identify any problem spots
My initial thought would be that something is happening where the javascript is erroring out (un-caught) and aborting the async postback.
If you can get this to happen in a development environment, you might want to try error handling the window.onerror event and throwing some alert boxes up. It might help to see where possible errors occur.
have you tried:
ScriptManager.GetCurrent(this).RegisterAsyncPostBackControl(yourButton);
It's seem to me, you have issue with Update Panel.
Define the following properties of Update Panel if you are using more than one update panel and updation of one panel change the data of other update panel.
For the UpdatePanel
ChildrenAsTriggers = true
EnableViewState = true (if you are using this feature)
UpdateMode = Always
Use the same properties for other update panel in your same page.
If you find it useful, please mark it as your answer else let me know....
Try commenting out Update panel if any. Then try to click button there must be some error on the page. I've also faced similar issues.
In my case none of the events (either button or check box) were firing. I was able to overcome by this problem using following way.
In my master page I had closed a tag referring to an external .js file with /> notation instead of <script></script>.
for Ex: chanage <script src='../../Scripts/common/menu.Js' type='text/javascript' /> to <script src='../../Scripts/common/menu.Js' type='text/javascript' ></script>
Hope this will help you,
Ramesh
Related
I don't really know where to start with this one. I am getting:
`Failed to load viewstate. The control tree into which viewstate is being loaded must match the control tree that was used to save viewstate during the previous request. For example, when adding controls dynamically, the controls added during a post-back must match the type and position of the controls added during the initial request.`
after moving a website to a new server. The exact same code works on my other server. It happens when I submit one of my forms (but doesn't do it on all form submissions).
Any ideas what can cause this so I have somewhere to look?
Using: ASP.NET 2.
EDIT: I am adding some user controls to a placeholder dynamically at runtime but this same code is working ok on my other server. I have tried clearing the controls in the place holder before adding new ones (as I saw a post about that) but it hasn't helped.
EDIT2: It seems that the postback is just failing. It isn't going into the onClick code of the button either so something is deffintiely screwy .. If I try / catch the exception it seems that all the controls are still added successfully ... Setting my Dynamic UC's to EnableViewState = false resolves this particular error.
EDIT3: Ok, I think I may have a handle on what is happening. For some reason on the old server the form action is default.aspx?action=amend but the new server is showing amend.html?action=amend so I think the re-write module is messing up in IIS. This would explain the control adding issue as well because the action is happening 2 times (I think). I will look into the Rewrite module and see if anything is wrong then post back.
Please, have a look at these articles:
http://blog.typps.com/2008/01/failed-to-load-viewstate-typical.html
http://weblogs.asp.net/guys/archive/2004/12/05/275321.aspx
Or try a simple temporary solution - disable viewstate for this placeholder. Either way, I'm puzzled why it actually works on your first server. I'd be glad if someone else will be able to clarify this subject more.
It turns out that the post back Url for the form is wrong on this server (unsure why at the moment, I will update when I know). This is causing the dynamic controls to be added in an unexpected way and causing the error. I noticed this when I managed to post my form and the content didn't update. I manually adjusted the action url using firebug and all is well.
Worth looking at walther's answer regarding dynamic controls and the viewstate though.
Not sure what caused it but I am manually setting the form action in the page load now and it seems to have solved the issue.
I having an issue with the ASP.NET Treeview control. I create the treeview just fine but the nodes will not expand or collapse. I see there is a javascript error but it is for line 1 character 0 of the webpage, there is nothing at line 1 character 0.
I am using the ASP:Treeview control in conjunction with the Telerik controls, but I'm not sure if that is an issue.
I saw there was a similar question here but the answer is not pertinent to my site. Has anyone run into this issue before? I've tried searching Google and tried a number of proposed solutions but so far none have worked.
Thank you,
Normally with problems like this it is best to isolate the code which is causing the problem. For example, create a minimal page with no other controls or external JavaScript and see if the problem persists.
It's also useful to use a decent debugger. The latest IE8 actually has a very good Visual Studio-style JavaScript debugger built in - go to your page, hit F12 and the go to the Script tab and click 'Start Debugging' and see where that leads you.
I've seen unhelpful javascript errors when a page does an AJAX postback, an exception occurs on the server, and the client javascript is unable to handle what the server returns. You could ascertain if this is happening by debugging the site, putting a breakpoint on the Page_Load method (or something similar), and see if it gets hit when trying to collapse or expand the TreeView.
We have a user who is having problems with a ASP.NET app. The user hasn't been available to gather many details, but at this point our best guess is that the PostBack is not occurring. Something is going wrong between when the user clicks the LinkButton and when the HTTP Request is supposed to be made.
(User does have JS enabled)
Beyond solving the immediate problem, it might be helpful for posterity to assemble the canonical list of things that can break PostBack behavior of ASP.NET controls.
If you have say a button that has a postback event as well as a javascript event on click, if the javascript event that is fired returns false postback will be stopped.
I would first check that your <form> tags are well formed and that you don't have nested <form> tags. Both times I've debugged something to do with postback this turned out to be the problem. It's confusing because it's a browser dependent issue.
Having a self-closing <script /> tag can stop postbacks occurring. Get the user to send you any javascript errors from their log. There is actually a decent JS debugger in IE8 (about the only good thing in it!).
a form with no method attribute, or method note being set to POST
an onsubmit event handler that does not return true
trying to submit the form programatically, but unable to locate the form by id as there is another element with the same id on the page
On a rather complicated screen with a big updatepanel, I'm running into the following problem:
If a user clicks on a certain button 6 or 7 times really fast, it seems to eventually process the last request out of turn and problems occur. Specifically, there's an xml document in session state, and it gets out of sync.
What I really want to do is block clicks to this button until the postback completes. I know I could probably find an easy way to do this with Javascript, but it seems like it might be built-in.
Any thoughts?
Note: The answers below are helpful, but they haven't solved the problem. After disabling the linkbutton with onClientClick and then allowing it to come back after the postback enabled again, the problem persists. It's almost as if the updatepanel isn't quite done with everything even though it has drawn the fresh, enabled linkbutton on the screen.
More notes (solved!): I solved this one by using BlockUI (jQuery plugin). See my answer below.
ASP.NET UpdatePanel always honors the last request. If you make a request while one is processing, the first requests gets terminated and the current one is processed. It was designed and built to work this way.
I would disable the button with JavaScript once it has been clicked.
UpdatePanel? I will assume you are using MS AJAX, if so I will recommend you download the AJAX toolkit if you have not done so. This toolkit comes with many ready to use controls, and extensions to help you in your AJAX enabled app. For example, there is one extension called "ConfirmButton" that will help you prevent the user from clicking in a button more than once, and it also does it in a very cool and elegant manner.
Another option will be to use JavaScript or better yet, create a custom button control that has a property to be disabled after it is clicked, if you do that, it will be really easy to reuse it in your other applications.
Hope this helps.
In a home-rolled AJAX framework I worked on awhile back, we simply logged the last call in javascript (javascript function call with many parameters) and prevented subsequent calls with identical parameters. It wasn't ideal, but it did the trick in a pinch.
I was having some "Asyc" problems with infragistics control, but after adding ScriptMode="Release" in Scripmanager the problem was resolve.
The link below solved my problem in about half an hour. Just going with a javascript disable (and I tried several different ways...) did not do the trick due to the timing of the updatepanel.
Disabling UpdatePanels While an Asynchronous Postback is in Progress
We got strange error last days. ___doPostBack is undefined.
We are building quite advanced website, but not using postbacks much. One of place where postback used is ASP.NET Login Status control.
It is probabalystic, sometimes it is rendered, sometimes - not. For IE, Chrome it works mostly fine, but from FireFox it is quite high chance not to have doPostBack in page source.
Any ideas?
PS: In addition, error happens only on live environment, which uses Windows 2003 & IIS 5.0, dotnet framework is 3.5
Can it be because I am using OutputCache on page level?
Just happened to us: When googlebot or any other bot hits your page before a regular user, the page is cached without any postback options.
We did a simple hack, using different a outputcacheprofile if the request.browser.javascript is false (asp.net sends different versions of the page to those browsers/crawlers/bots)
I had the same problem, but I realized that ASP.NET does not render __doPostback when server controls don't need it.
When I put a gridview or linkbutton that need __doPostback, ASP.NET rendered it.
Yes it might be about the output cache, comment it out and try again please
Usually this happens when you have malformed javascript somewhere on the page (usually, before the __dopostback function).
Have you viewed the page source and looked to see if the __dopostback function is actually rendered in the page, regardless of whether you're getting the error or not?