Web Forms :: Controls Missing Values After Postback?
Sep 23, 2010
I just uploaded an asp.net webforms site I've been working on to my ISP's servers. I have a simple page that allows users to enter schedule data. The problem is that when the user clicks the Add button and I try to process the values they've entered in the textboxes and dropdownlist in the click event handler, all the values are blank. For example, there's a DropDownList called uxStartTime on the page and after postback uxStartTime.SelectedValue is blank. However, the Response.Form[uxStartTime.UniqueID] has the proper value. I have EnableViewState="true" in the aspx page. This all works fine on my local machine, just not on the server. Can anyone tell me what's going on? I can use the Respons.Form syntax, but it's a little more verbose and prone to typos.
I have an ASP.NET TextBox with TextMode = TextBoxMode.MultiLine that is used within an AJAX Update Panel. The .Text value has been pre-set to a value that has multiple lines.
When using Chrome(7.0.517.41) or Firefox(3.6.11) working with the controls posted back value on the server the carriage return is lost if the user hasn't edited the pre-set value.
Im not sure what i could have done wrong here but i created a dataset (ran a query and it returns the correct data) - created my BLL class - bound the ObjectDataSource to the control using the BLL - ran the site and all the data is showing as expected. Now i click edit columns (from DetailsView smart tag) and the selected fields are empty. I refresh the schema and this makes no difference. What could i be doing wrong?
While generating dynamic controls like , textboxes, dropdownlist, checkboxes and radiobuttons, after filling the textboxes and etc and submit and then postback occurs, the dynamic created controls missing. I try to find a way to make the controls persist for validation checking. Tried to use Viewstate to store the pnlTextBoxes and etc, but it has serializable error.
I am having an aspnet panel in my aspx file.There is an ultraweb tab placed inside this.also I am having a button outside this panel.Within the tab I have a textbox whose readonly property is
set to "true".Whenever I click the button a javascript function is called .On clicking 'OK' in the popup ,the textbox values are lost.Is there a way to retain these values?
Im binding the gridview in page load.After i click the link button in the gridview it displays another gridview.I have a checkbox in that gridview.I check some of the checkboxes.while i click the save button i want to get that checkbox state whether its checked or not.Bt for me its showing no records in the grid.How do i persist my data and get the checbox's state.
I know that on a postback all controls are rerendered.My problem is that I have an page who holds panels who holds web user controls who holds itself x time an panel with an web user control.I have an action that takes an postback and it resets all the design of those web user controls, but not the controls of the main page.What can I do to save the current state of my page ? The current panel that is visible etc.I tried a simple update panel without success by setting UpdateMode to conditional and ChildrenAsTriggers to false.
I had successfully created a functionality where I can dynamically add rows and columns to a asp table by creating/re-creating controls on every page load.
I have 2 buttons - Add rows and Add columns that, basically according to a asp.,net page life cycle, occur in the following order and work perfectly fine.
Page load is fired and controls along with their viewstate are recreated. In Add row button click event - I just create a new table row and add controls to each cell dynamically.
Same thing with Add column, Delete Row and Delete Column button click events.
However, now I added a Dropdown which when its index is changed needs to retrieve values from the database and create controls based on those values and then also bind the Db values.
But it doesn't work correctly since the asp.net page cycle cannot capture the dropdown's selected value in page_load as the page_load fired first and then the selectedindexchanged event is fired later, the controls are not created.
I don't know how to handle this scenario and incorporate it into my existing code.
I have a gridview with a dropdownlist in one to the headers. So on the onselect event of the dropdownlist I want to change the assigned values of itemTemplate values inside one of the columns.
I have a series of jQuery dialogs that contain ASP.NET form fields. I have a hidden ASP.NET button that is triggered when the user clicks a button in one of the jQuery dialogs. I can enter some data (listboxes and textboxes) and click the button that triggers the hidden button's event (an onClick) and the page will post back.
But, when I put a breakpoint in the onClick event in my codebehind I see that the form fields (reportTypeListBox.SelectedValue, etc.) just have the default values instead of the ones I entered. This happens unless I take the form fields out of the jQuery dialog, then it works perfectly.
I have another jQuery dialog that contains a ASP.NET textbox that is basically doing the same thing (triggering a hidden ASP.NET button with an onClick event) that works properly. The only difference is that its jQuery dialog is not in a seperate javascript function. It's right in the "$(document).ready(function () { }." While, the series of dialogs that are having trouble are in a function called "openDialog(selector)."
In my web application i am setting the EnableViewState="false" for particuler page. In that page i am having two dropdowns,this dropdown binding the data in Page_Load event. So when i am clicking the button that two dropdown values are getting celared. see the below sample code.
I allow the end user to create a tab control dynamically in an ASP.Net page by getting some details. For each and every tab added I get some settings -
Tab Title Tab Content Tab Footer link
So I get these details for each and every tab. The user is provided with a button 'Add Tab' to more one more tab. So I need to add one more tab settings panel in the page to get the tab settings. But doing so, I lose the values entered in the previously created dynamic tab settings panel. The user can add as many tabs and enter settings for each and every tab. Finally when they save it I build the tab control (based on their settings and content) and I render the control.
Since the controls are dynamic, I'm able to thing of two options -
Recreate previously created n - 1 tab settings panel while adding a nth tab. So across each and every postback I need to recreate the settings panel for each and every tab. But I don't know how to persist the values in this case.
Add the settings panel in the client side with simple html controls and on page UnLoad parse the controls -> Parse the settings -> Save it in a hidden field -> Get it in the server side. In this case I lose all the server side capabilities where I need to write validation scripts for the controls.
I've created loads of user controls, but this is my first time dealing with extending a server control. The problem I'm getting is that the base control's data is not being persisted across postbacks in a Master/Content page.I'm actually trying to get this working using a Telerik control (for my sins), but the same issue happens with a standard Web TextBox control. Code:
[Code]....
Now, I've copied the way I handle the control state as I do it with user controls (ControlState), and it isn't working. Can someone point me in the right direction please? All the examples I find refer to creating user controls, not extending existing controls. Specifically why nothing is being persisted on post back.
I have a page with an panel on it that can contain a number of editable controls (textboxes, date pickers etc). This panel (and the controls) are populated dynamicaly by loading up an XSLT tranformation and applying it to an XML document (which represents the entity being edited) in the Pages Load event if !isPostBack.
Once the user has made changes they click a button and the form posts back. At that point I want to be able to go through the various controls in the panel, get the updated values and persist them back to a database. When I try to access the controls in the underlying buttons even theyre not there the panel is empty.
What I think is happening is that the page is being recreated at the start of the post back. When its recreated the XSLT transformation doesnt run because its a postback so the edit panel never gets repopulated. The controls therefore dont exist as far as my Button handler is concerned and it cant access their values.
My stopgap solution to this is that Im not checking isPostBack before repopulating the panel, so now the panel gets repopulated in the post back, the controls are there and Im able to query their values. The problem is that this involves another round trip to the database server to pick up the xslt and thats undesirable.So, first of all, have I understood the problem correctly?
I could save the trip to the db by storing the xslt (probably in the view state) but the whole idea of having to load up the control before checking its values feels sort of wrong and Im concerned that Im doing the wrong thing without realising. When I repopulate the control I am, of course, applying the XSLT to the XML document as it stood before the user made any edits. I would have expected querying the value of a control to return me the value before the user changes, but it actually seems to return me the value of the control as it was in the page when the user clicked the button. How can that be?
How Can I retrieve values from TextBox before RowUpdating function is fired? I have GridView with update panel which is sorted by two dropdownlists and I need autopostabacks to filter and bind gridview. Now I want to update row in my gridview but I can't get values from controls I'm getting old values from database. Do you the way that I can use values from controls before updating the row?
I created a ASP.Net page with dynamic controls. These controls are added by the user. In the Page_Load event a table is created with few controls.
When these dynamic controls do a postback, I can't get the values of these controls, because in my HTML code they are not available.
I only get the id of the control which triggers the postback. But I can't find it with the command FindControl. All other controls, which a are not added dynamicly are searchable.
I have some problems with trying to read values on a postback. The fields, textboxes and dynamiclly created fields doesn't keep their values or I'm doing something wrong when trying to read the values. I get an error message:
System.NullReferenceException was unhandled by user code Message="Object reference not set to an instance of an object." Source="App_Web_m-6qot6q" StackTrace: at Sikt.RäknaVärden() in C:Visual Studio 2005WebSitesKalibreringscertificatSikt.aspx.vb:line 688 at Sikt.Button1_Click(Object sender, EventArgs e) in C:Visual Studio 2005WebSitesKalibreringscertificatSikt.aspx.vb:line 892 at System.Web.UI.WebControls.Button.OnClick(EventArgs e) at System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) at System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler.RaisePostBackEvent(String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String eventArgument) at System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) at System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint, Boolean includeStagesAfterAsyncPoint)
Also, I get some other errors, such as "Name 'DropDownList1' is not declared" and "Name 'Label1' is not declared" I'm used to classic ASP and this is my first .net 2.0 (vb) application. I'm including some of the code (should be all relevant code)
I am using string builder class to store the dropdown selected values .. I am doing this on the selected index change event .. The problem is the previous value does not retain ..
i want to hold data at runtimeEx-I have a 3 Services A,B,C and in A,B,C contain services list,then if user select A service and 3 services in a A Listagain user select B service and 2 services in a B Listand again user Select C Service and select 1 services in a C listSo How i can hold data A,B,C services ID'S value with respect to services listID'S value at runtime.
I'm constructing a User Control that will have one Property called "ContractIdx". Here's how I've constructed this Property:
public int ContractIdx { get { return Convert.ToInt32(this.Attributes["ContractIdx"]); } set { this.Attributes["ContractIdx"] = value.ToString(); } }
I'm initially loading the User Control by passing a parameter to it and setting ContractIdx accordingly. That all works fine.
Upon Postback though I'm loading the User Control without any parameters and then setting its ID property to what it was before the Postback. My understanding was that if I did this then ViewState would properly restore everything. Yet apparently this is not the case with the "ContractIdx" attribute.
Where am I mistaken in my understanding? How should I change things to get this mechanism to work?
I have a form with 2 sections. The first one contains some radio buttons. The second one contains a checkboxlist. When we change the selected radio button then it modifies the elements in the checkboxlist. For this I setted the radio buttons with autopostback, and in the code behind (in OnLoad) I populate the CheckBoxList depending on the selected radio button.
This work fine.
The problem is that I also have a button at the end of my form which post the data of my form in another page (with PostBackUrl). Then in that page I would like to retrieve the values of the checked checkbox. But I can't find how to do that. In the Request.Form I don't see anything.
I searched on the web but I didn't found really a solution.
