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Dynamically Created User Control's Dropbox Items from Database resets on postback

First off, I have managed to create a web application where my dynamically created user controls are recreated and repopulated with the correct information upon postback. I am not sure what my problem is, but i hope that you will be able to help me figure it out based on my situation:
On my page i enter the number of controls to be created into a hardcoded textbox (its on the aspx page) and click the okay butten. This in turn, creates the specified number of user controls dynamically using c# in the background.
So far the desired number of dynamic controls are in a table on the page.
Next...
I have 1 textbox and 4 dropboxes on each dynamic user control. When i type a company name into the textbox field and press enter or click away (on text changed event) it autoposts back and the textbox retains the company name that i have typed in.
Based on this string the dropboxes are populated from the database. Now when i select the desired items from the dropboxes and click on the save button (located outside of the dynamic controls, on the page) it does an insert to the database, but it turns out that upon this postback the indexes from the dropboxes have been reset and the wrong values get inserted.
The following pictures show firstly, how it should be and then how it is.
Basically the company name remains in the textbox of the dynamic control, but the information i choose from the dropbox resets to the first index.

It's hard to tell what happend without code, but this is a common mistake:
If you fill/create the dropdownlist controls in the page load event and you post back, the code will refill/recreate the controls. That's why you have to use something like If(!IsPostBack) in your page load event. Otherwise it will execute that code everytime you do a postback and actually just want to execute the code in your event handler for that button.

If you're dynamically creating the controls, make sure to do that in the Page_Init event. Dynamic controls have to be recreated on every postback. Their state is restored after the Page_Init (if it is a postback), so make sure to only set their values in Page_Load if you want to overwrite them.

How to append controls to a panel?

I am developing a dynamic website in ASP.NET. As a trial I tried a code shown below, that adds some controls to Panel1. When user clicks a button for the first time the controls are added to the Panel but when user clicks the same button for second time, the previous controls are replaced with new ones. But I want the controls to be appended one after the other each time the user clicks the button. The code is something like this:
Control c=Page.LoadControl("DData.ascx");
Panel1.Controls.Add(c);
I also tried
Control c=Page.LoadControl("DData.ascx");
Panel1.Controls.AddAt(Panel1.Controls.Count,c);
But this replaces the first output. Please tell me how to append these controls?

As you would expect, this appends a single control:
Control c = Page.LoadControl("DData.ascx");
Panel1.Controls.Add(c);
You can append as many controls as you wish in this fashion.
However, you need to keep track of the controls you are adding in some persisted/stateful fashion (database, Session, ViewState, etc.).
You need to rebuild the control tree every time the page loads.
See my answers to similar questions:
https://stackoverflow.com/a/10050755/453277
https://stackoverflow.com/a/9545079/453277

It may be about the life cycle of asp.net page. Each time when page loads it returns to the initial state. Button Click events are handled after page load and you have only one control at the page. Please look Button to dynamically add controls everytime it's clicked

How to know at page load, if view state is clear at some other event on the page?

I am facing a weird problem, i am dynamically loading user control at page load with ViewState condition check, if true then load it, else not.
Now the problem is on a dropdown selected index change event i set NULL to view state but the page load comes in action first and it sees that the viewstate is not null, so it load the control again, how to overcome with this problem, please let know how to fix it.

Why don't you load the user control at page PreRender event. This should resolve your issue. If not please give the page behind code.

Set a boolean and save it in the viewstate? It's not pretty but neither is webforms. :)

Wrong state in Server Controls with same ID's when dynamically adding UserControl to UpdatePanel

Here is what I am trying to do. I have a page with two link buttons and an updatepanel (the two linkbuttons trigger the updatepanel). I have two usercontrols which have labels with same ID's. When I click the first link button, I add the first usercontrol to the updatepanel and set the label value to datetime.now
when i click the second link button i add the second usercontrol but i see that the value of the label from the first control is set in the label in second user control. if the id's are different there is no problem - but in my case the usercontrols are being developed by different teams and I am integrating them in the way i mentioned - so they may have same ids.
i have browsed all over and tried various suggestions but i cannot get this to work, any help will be greatly appreciated.
Thanks
Job Samuel

Your problem has nothing to do with the UpdatePanel, actually.
Imagine what would happen if you had a 3rd LinkButton, which did nothing but postback. What would happen if you clicked the 1st LinkButton, the UserControl appeared, and then you clicked the 3rd one? What do you expect to see? If you think you will see the UserControl again, you are wrong. Dynamically created controls must be created every request, they don't stick around automatically. ViewState remembers the state of controls on the page, NOT what the controls themselves are in the first place -- thats what the markup in the aspx page does. Dynamically created controls obviously arent in the markup, so they arent automatically recreated.
You need to think of the lifecycle of a control as 'straddling' half way between two requests. It starts half way into one request and ends half way into the next. You need to save which user control is currently displayed in either a hidden field or a Page.ViewState value (not the user control itself mind you, just whatever information you need to figure it out), then reload that control from the page's OnLoad. If you do that -- the sequence will go like this:
(1) Click LinkButton1
(2) UserControl1 dynamically created
(3) Click LinkButton2
(4) Page.OnLoad reloads UserControl1
(5) UserControl1 loads its postback data and viewstate
(6) LinkButton2's click event fires
(7) Remove existing UserControl1 and add UserControl2 dynamically
(8) UserControl2 can have the same ID, since UserControl1 already 'consumed' its state.
I suggest you browse my series of articles on Understanding Dynamic Controls in ASP.NET:
http://weblogs.asp.net/infinitiesloop/

You have to set a different id for the label when you create the user control.

Using Page.IsPostback Within a User Control Wrapped in an Update Panel

I have a main page into which i load a user control with a grid and add/edit link buttons.
If I bind the grid by setting the datasource and calling the databind() method in the page load event then it sets properly. However, I want to keep the selected row between postbacks, so I wrap the bind code in "if (!Page.IsPostBack) {}" as usual. My problem is the page load always registers it as a postback and my code never runs.
I am using the 2.0 framework, and my grid is an 2008.1 Infragistics for the 2.0 framework.
I thinking this must be something simple.... or hoping anyway!
Thanks in advance

If you place your control into an UpdatePanel, then you should check for Page.IsCallback instead of Page.IsPostBack.

The two ways I found round this were:
to load the user controls when the page is first loaded and then hide them until user selected what they need to see.
to load a new page into an iframe on the main page allowing it to have its own page control meaning when its loaded in at first its not a postback.
Not the greatest, but gets by.
Thanks for the help.

I have mixed feelings about necroing a thread this old, but the question is still relevant, and there weren't any great solutions offered, so though I would add what I recently did to solve the same issue:
I had a similar problem with a site I was building. My solution was to add a method to the user control called "OnFirstLoad" that does all of the stuff I would have wrapped in an "if not Page.IsPostback" block. I then call the "OnFirstLoad" method from the hosting page the first time the control is loaded into the control tree. This way the control itself doesn't have to worry about whether or not this is a postback, and the main page can initialize it as needed.