Im using ASPxPopUpControll in which I have ASPxCallBack panel. THis CallbackPanel was embeded there because I wanted to have solution based on callbacks despite of reloading page each time.
In this CallBackPanel I've embeded asp:Wizard control.
What I want to achive is get rid of postbacks after clicking next previous etc buttons in this wizzard.
Any hints?
Maybe there is other way to create nice wizard without any postbacks ?
thanks for help
The ASPxCallbackPanel cannot intercept postbacks and "convert" them to callbacks as the MS UpdatePanel does this. So, a possible solution is to replace the ASPxCallbackPanel with the MS UpdatePanel and use the Wizard inside it. One more solution is to use the ASPxPageControl, position all required controls in its Pages and manage them manually.
I would recommend looking into ajax and jquery for asynchronous postbacks, that way you don't get a page refresh and you would only need to update a smaller part of the ui.
Related
I have a search button in a asp.net page that show a pop-up and by closing that some controls are be added to a panel in my form using AjaxManager of Telerik.
I've used the Telerik:AjaxUpdatedControl to say render the panel everytime a search is done.
But my proble is when search is done for second time the controls that had been adde for first time will be removed.
how can I overcome this problem?
Dynamic controls are not created after a postback. You have to recreate them every single time. (Their viewstate is still maintained you just have to create them with the same ID and in the same place within the control hierarchy).
The DynamicControlsPlaceholder control does this all for you. It is available at - http://www.denisbauer.com/ASPNETControls/DynamicControlsPlaceholder.aspx
However I would suggest you use it for as little as possible. Heavy usage of it can cause performance to suffer.
In my page I have a 'Button' when I click it, it loads an instance of my 'UserControl' to a 'PlaceHolder' .. I've used the 'UpdatePanel' but it was a hazard! .. I think it's because the Asp.Net 'Ajax' sends the whole page to the server and behind the scenes it actually causes a full PostBack. and it will help me if I could implement a partial PostBack so I won't need to save or access my database each time I reload or click the button to re-assign the values to my UserControl.
So I was hopping for some samples implementing a partial PostBack to load only one instance of my UserControl.
I can't post the code in my page here because it's a REAL MESS! .. but if you really need this to help me then maybe I could send this and post a clean solution here on the question.
Thanks for your time .. I hope there's some simple answers to my question because I'm really hopeless here!
The UpdatePanel always causes a postback to the server for the entire page, and only updates the UI's within the update panel. That's just how it will always work. If you only want to load a user control, consider using a JQuery approach to pull the user control from the server and render it via client-side JavaScript.
http://www.codeproject.com/Articles/117475/Load-ASP-Net-User-Control-Dynamically-Using-jQuery
http://samuelmueller.com/2008/12/dynamicloader-plugin-dynamically-loading-asp-net-user-controls-with-jquery/
HTH.
I am struggling with finding clear answers to dynamically creating the same page over and over. The questions and samples I have found seem to be all over the board on this topic. I have studied the life cycle and still seem to not have a clear answer as to where code should go.
I have a master page and a content page. All the content in the content area needs to be dynamically created (text boxes, ddl's, page tabs, buttons/onclick etc.).
After a user fills in data and clicks a submit button, I need to read the values off the form and rebuild the page completely again (not add/remove controls to current content).
My question is then.
Where do I put my code to build the page?
Will this area allow me to use IsPostBack so I can rebuild content with Request.Form values?
Will my buttons _Click events work?
Are there any working samples out there you could direct me to?
Thank you very much for the feedback...
I don't know all the answers to your questions, but I hope this may get you started. When dynamically generating the UI through code, this happens in Init. Controls dynamically loaded on Init is key because between init and load, on postback, viewstate is loaded for these controls.
This means you need, on every postback, recreate the page as is to match the previous control tree, then deconstruct it after init and recreate the new UI, if something is supposed to change UI wise. This is because it validates the tree structure to determine its the same UI. Now, if you don't need viewstate, this may not be as much of an issue. I haven't verified this without viewstate to see if it behaves different.
It depends how dynamic you need it, whether you need viewstate (is a big factor).
HTH.
Try creating the controls in the page's PreInit method. "IsPostBack" should work and the click event handlers should work as well.
What you need is a web user control, see ASP.NET User Controls
Brian's advices are good and you should follow them.
This might not really answer your question but still I add it as an advice. I'm professionally creating ASP.net web applications at quite a large scale and from my experience I can say that too much "dynamics" is usually bad and should be avoided because it just introduces complexity. Normally you might want to expose UI parts into ASP.net UserControls or if you want to make them even more reusable (if that's a factor) then into ASP.net Server controls. Then you replace different of them dynamically rather than creating everything from scratch.
How can I create a <form runat="server" /> with code (c#)? My problem is that I want to have multiple forms on my page (and none initially). I'm loading all components from db.
I've looked everywhere and can't find anything about it.
From painful memory, working with multiple forms in ASP.NET-webforms is a real pain. Maybe consider looking at ASP.NET-MVC which is much closer to the HTML; consequetly you can do anything you like re forms; just use a foreach in the view, writing a form for each item.
ASP.NET page can have only one "server side" form.. that's one of the "core" rules.
So you'll have to find other way to achieve what you need.
You can work with UpdatePanels and "submitting" specific panel should send only its contents, ignoring the other data in the form.
ASP.NET only allows for one serverside form but allows multiple regular forms in one page. I suggest you read this article: ASP.NET Forms.
Thanks for the replies. I solved it using this inside my Page:
public override void VerifyRenderingInServerForm(System.Web.UI.Control control)
{
}
And then render my form with plain text.. Can't see any errors yet, but will update if any turns up.
Also, as I said in my question, I'm loading all control dynamically and I don't use any code behind with the controls (if I did, I guess some errors would turn up). All my post are handled by checking against HttpContext.Current.Request.Form.
I'm trying to convert a classic ASP page to ASP.NET 3.5. The page has several forms on it for several different things.
In ASP.NET, there's a server form control wrapping the entire page, and form controls don't work within a server form control, and you can't have more than one server form control on a page.
So in order to keep this functionality, I can either:
Remove the server form control that's wrapping the page, and leaving the html forms on the page.
Create button click events for every form and perform the POST in the code-behind.
What's the preferred method here?
I wonder if converting to vanilla asp.net (aka webforms) is a bad idea here. Personally I'd go to MVC instead - allows multiple forms etc, and the views are much closer to he HTML, a lot like ASP.
I guess I'm saying there are some glitches vanilla asp.net introduces that you don't have to suffer.
I would go with the second option, any button click is going to post the whole page back anyway so you're not saving any bandwidth. Simply handle each button appropriately.
Check the answer I provided to a similar question here :-)
How to get past embedding a html form for paypal buttons asp.net
If you're going to use different button clicks, you still need to use this override to disable the non-related buttons in each handler, otherwise it won't work. You can only have one form tag at a time - this way you can toggle/disable the ones you're not using as appropriate.
Better still, refactor your application to use a single form. While MVC would be a closer match to the model you're using right now, it wouldn't make sense to go that route unless you were experienced enough with it; Web Forms is an easier jump.