C# - Persisting Dynamic Controls Over Postback?
Sep 30, 2010
I have a datagrid that loads on page_load.
In this instance I can't load the datagrid in page_init as the results of the datagrid are determined by a checkbox and the checkbox would always be set to true during page_init to the viewstate not being loaded.
I have an OnItemDataBound event on the datagrid that dynamically creates controls and later on I want to access the value of some of these controls (e.g. a text box)
Of course the problem is I can't access these controls values as they don't persist over a postback.
View 1 Replies
Similar Messages:
Mar 14, 2011
I need some high-level advice on how to deal with this issue. I want to have dynamically created buttons, each with a different CommandArgument, that call an OnCommand event when clicked. Given that these are dynamic buttons, I have to re-create them in Page_Load after the postback. However, when I re-create the buttons, the orginal command arguments are lost, and the arguments generated after the postback are only valid.As you'd expect, if I don't recreate the buttons, the event handler is never called because the buttons don't exist.My question is, how can I retrieve those original commandarguments, without the use of sessions.
View 6 Replies
Sep 21, 2010
how to make a control that can have controls nested inside it. I've made a jQuery tab browser class which uses a hidden field to remember which tab is selected and create the relevant client script to re-select it on postback...it works fine...
This is for web part development so all controls are created dynamically.
The problem is when I add a control to one of the tabs, the values set in that control disappear on postback..I understand there is a lot of information about user controls, viewstate and control state but nothing seems to give me access to those values...
I've boiled it right down to the basics and still can't get it to work unless the custom control has all its controls added in OnInit...which is bad news for me because I need to instantiate the browser, the use a 'AddTab' method to add tabs and controls to them, which occurs after the OnInit event and therefore I can't access the postback values!!
I get the feeling I'm missing something big here, I must be lol...here's is an example:
[Code]....
These controls have to be dynamically created, so I didn't see the need to make the ascx user controls..
View 4 Replies
Jan 17, 2010
how i persist the selected date of calendar control on Postback iam displaying Dates from database in to Calendar control and when page postback then nothing is heppening . How i persist the selected dates on Postback may i have to use Session or some thing like that?
View 5 Replies
Jan 25, 2011
I have an ASP.Net Application that in some cases will create up to 100 or so dynamic controls that have events being triggered from CodeDom Assembly. The problem is when at an event is fired off I have to Re-Create all those controls on a PostBack. With 10 to 30 controls its not so bad but with 100 it takes approx 3 to 4 seconds before the user can resume filling out the rest of the controls.
View 2 Replies
Feb 15, 2011
I have a page to wich I had several controls dynamically. When the page is posted back via Ajax, the values of the dynamically control do not make it server side. However, everything works well if the page is posted back in the normal way ( without Ajax).
I need the post back to be done via Ajax because I need to use the Callback function to perform other tasks in the UI once the call returns.I found this excellent article but it doesn't discuss ajax:
http://www.4guysfromrolla.com/articles/092904-1.aspx
View 17 Replies
Mar 15, 2010
I'm trying to create a page that will display a survey that has multiple pages... everything displays fine, but I'm doing something wrong on the timing as my dynamic controls (for the answers) are disappearing when I post back. (so I can't get the answers or perform validation)
1) I have a Repeater control on my page that is populated in Page_Load !IsPosBack that is acting as navigation. It displays each page name, and each Repeater Item contains a LinkButton whose OnCommand event does:
2) There is a second Repeater on the page that is populated with Questions corresponding to the selected Page (from the step above) This is just a DataTable created and then DataBound to the Repeater.
3) The Questions Repeater control has an OnItemCreated event that dynamically generates the proper control for the Answer (TextBox, DropDownList, RadioButtonList, etc...) and places that control in a Placeholder in the Repeater Item.
This all works for displaying, but when I attempt to click a Button, I cannot access the controls generated in step three, and all of those controls disappear from the Repeater.
I have tried creating databinding the Questions repeater in Page_Init as well as dynamically creating the answer controls in a (foreach RepeaterItem...) statement as opposed to OnRepeaterItemDataBound... but now my buttons (located in the FooterTemplate) refuse to post back at all...
added a Test button for postback, but that doesn't work either.
View 3 Replies
Jun 18, 2010
I have this problem of handling postback for controls built dynamically.
I am having something like this:
[code]....
Now, whenever it posts back, the control disappeared. If I remove the !IsPostback, then it will always create the control.
View 2 Replies
Jan 11, 2011
I'm inserting controls dynamicaly on my page on pre-init, thease controls are inserting based on a dropDownList that load its values from a database. These values are diferent to all clients.
If I insert my controls on pre-init then I have access to the value of radiobuttons, but this insert only 1 controls cause in pre render I don't have the selected value of dropDown.
If I insert my controls on on-load event then I have the value of my dropDownList control so I can be able to inser the correct number o controls but I don't have the value of my auto-postback radioButtons.
I make a project to solve this and I share the code of it here. (VB.Net 4.0)
Front Code:
[Code]....
View 7 Replies
Jun 15, 2013
I have created a web form in which i have used user control there is link button on different link button user control loads . i have added dynamically webcontrol to that link button . they are loading properly but when i try to save data through one of user control on click of button the user control disapper from that place but when i put static user control to my page its working
View 1 Replies
Sep 21, 2010
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.
[Code]....
View 1 Replies
Dec 15, 2010
I have several dynamic user controls,that I want to load them in seperate tab panels.but my problem is when the postback occures my user controls disapeare from my tabpanels. however I want to keep my user controls in my tabs whenever I click on each tab.
View 5 Replies
Dec 21, 2010
When creating dynamic controls based on a data source of arbitrary and changing size, what is the official way to track exactly how many controls need to be rebuilt into the page's control collection after a Postback operation (i.e. on the server side during the ASP.NET page event lifecycle) specifically the point at which dynamic controls are supposed to be rebuilt? Where is the arity stored for retrieval and reconstruction usage?
By "official" I mean the Microsoft way of doing it. There exist hacks like Session storage, etc but I want to know the bonafide or at least Microsoft-recommended way. I've been unable to find a documentation page stating this information. Usually code samples work with a set of dynamic controls of known numbers. It's as if doing otherwise would be tougher.
Update: I'm not inquiring about user controls or static expression of declarative controls, but instead about dynamically injecting controls completely from code-behind, whether they be mine, 3rd-party or built-in ASP.NET controls.
View 1 Replies
Nov 8, 2010
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.
View 3 Replies
May 4, 2010
have an ASP.net 4.0 page containing a GridView, where during the Page_Init event I'm dynamically adding BoundField columns to the gridview. I also have some custom sorting and paging methods that I use with this gridview, which result in postbacks on the page. In Chrome, Firefox, Safari, and Opera the gridview behaves as expected. HOWEVER, in IE 6, 7, or 8 when I click to sort a column in the gridview, or go to the next page of results in the gridview, it does not bind on postback, returning nothing back to the browser. Again, in anything but Internet Explorer, paging and sorting (frankly any postback event) brings back the gridview in its expected state. I only have the problem in IE. Relevant snippets of my code follow, where you'll see my Page_Init event calling a method in my WebFunctions class to add the BoundField columns for the table I pass to it, and my Page_Load event that calls the method in the user control responsible for binding my dataset to the gridview. Initial page load works in all browsers, but postback loading of the gridview only works in non-IE browsers.
[Code]....
View 4 Replies
Dec 23, 2010
(Example code below)
I have a GridView. It has a 'static' TemplateField (in the .aspx page). I add and remove BoundFields to it depending on user preferences on postback. Affter the second postback, the template field appears empty.
Here is a stripped down mockup of what I'm doing. You can click the "Regular Postback" button as much as you want, and nothing bad happens. But if you click the "Recreate" button once-- it's all ok. Click it again, and the "one" column goes on Christmas break.
So is there something else I should be doing, or is this going to be a "halcyon1234 to code interface" error.
[Code]....
View 3 Replies
Mar 31, 2010
i am creating gridview with dynamic template, and the grid is disappear while postback. my code is below.
i am using GridViewTemplate class to generate Templates
Public Class GridViewTemplate
View 2 Replies
Jan 13, 2010
My datasource is an ado data table that I have convert to a new data table so that each row in the original table is now a column with 1 row in my new table. I then bind the new datatable and create dynamic template fields with a text box where I bind the values. My problem is, when I try and retrieve the values changed by the user in the rowcommand event, the template columns no longer exists.
Does anyone know how i can retrieve these values? I've read over and over that you have to rebind the grid on each postback when you use dynamic templates, but I'm not sure how to do that and retrieve the values entered in the text boxes on the client side.
[Code]....
View 1 Replies
May 13, 2010
I have a simple user control containing two text boxes which I am adding to placeholder on Button Click event. I am storing the number(count) of clicks in View state and running a loop using count to create all previously added user control. I am also adding IDs to each User control (appending "UC" and count). I have also checked in view source the ids are same each time they are created. I have another button which basically does an post back. I have EnableViewState enabled ="true" in all controlls all the way up to Page Level. My problem is that User Input does not persist on postback. Should this not be happening automatically for me?
View 2 Replies
Jan 20, 2011
I read this article first to try to solve this issue, but I am already loading the controls in the Init phase of the page, yet viewstate is not persisting. Any ideas as to why? (Of note is that this is for a custom module in DNN and I do have some AJAX update panels on the page, though this section is not within an update panel, for what it's worth.)
As an overview of what I've got:
1. LoadControl.ascx - based on reading query string parameters, determines whether to load the master or the detail .ascx.
2. Master.ascx
3. Detail.ascx
In my master control I dynamically load either a master or detail sub-control in the page_Init. The detail page has a treeview control and then uses a multi-view control to display the panel associated with the depth of the node selected on the tree. On the panel being displayed I have a cascading ddl within a detailsview control which initiates a postback to select the child ddl based on the parent ddl selection. However, when the page refreshes after the postback, both ddls have resorted to their default selection.
What is interesting however, and I just realized this as I am typing, is that the Treeview is populated when the page comes back from the postback, so that is only possible if viewstate is being persisted right? (See the page_load code and you'll see that Call PopulateRootLevel(intTreeUserID) which populates the treeview, is not called on postbacks....hmmm.
Any ideas as to why the treeview maintains viewstate but not my ddls???? But though the tree is populated, I do have to explicitly select the node again and set the panel that the detailsview control is on to visible again too....
Here is the dynamically loaded control code:
[Code]....
And in the Detail.ascx page load I've got:
[Code]....
[Code]....
View 6 Replies
Mar 29, 2011
I have a requirement as mentioned below: 1. There is a gridview containing a linkbutton field (lnkgdvMerchant)in one of the column defination as menioned in the mark up below :Please note the bolded line of code for more details.
[Code]....
View 2 Replies
Sep 18, 2010
you save data into a dynamic hidden field ,which is created dynamically during the handling of some postback event.what is the best way to retrieve it from this field upon a postback, (besides searching the request for the key of this hidden field and then retrieving the corresponding value as in the code below)?
protected void Button2_Click(object sender, EventArgs e)
{
bool found = false;
for (int i=0; i<this.Request.Form.Keys.Count; i++)
[code].....
View 1 Replies
Jan 17, 2011
As the title says , i'm looking for some kind of technology that allows me to dynamicly add & remove usercontrols.Without a postback ofcourse :)A link would be awesome , example code would be super!
View 1 Replies
Aug 5, 2010
I'm creating multiple textboxes dynamically bases on different criterias, after that every time any control is posting back to the server,
i need to regenerate all the dynamic fields.
What should i do to make the controls stay once added to the form even if a post back occurs.
View 3 Replies
Jun 27, 2010
Can i know that how can i get a dynamic dropdownlist controls's value after postback?
View 5 Replies
