State Management :: Avoid Viewstate In Page Load Event?
Aug 30, 2010
I haveMaster Page -> ASPX page -> User ControlUser control page is contains all dynamic bind controls (e.g Repeater) depended on ASPX Page (Only one parameter say ItemNo)The problem is, if I bound user control on page load event with passing respective parameters then it's create to much view state (I checked source file and it's almost 1.5 MB)In other way if I put one textbox, and a command button and I pass required parameter on button click and load the control then page size is ok (I checked and it's < 500KB)
Now here is the weird thing. First i am running it locally on the built in vs2008 web server.I load my control in fine, do a postback from a linkbutton, locally on my machine it all works fine, no issue.However when it goes onto my host, it falls over with the message:
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.Now i also load controls dynamically and use postbacks and things in the admin area of the site...and that works fine, however my front end just keeps failing? See the code behing below:
Using ASP.NET with framework 4.0.30319, changes to the ControlStyle of a ButtonField in a GridView are not saved in Viewstate. Examining the source code suggests that this is because DataControlField.LoadViewstate does not load viewstate for the ControlStyle.
It's possible to work around this by overriding SaveViewState in the closest container and saving the state there.
I have been getting this error a lot lately with some of my users, and I had a couple of concerns with view state and I have read so many articles but I am still lost..
1. I use masterpage on all the pages and I need viewstate for some of the pages but..
There is a page where a user will fill out the information and then submit this data to a cgi server, and it is where I get most of the Client Disconnected errors, what would happen if I disable viewstate when they click on that button?
Now when a user browses from one page to another, does the view state from the previous page get deleted? If not how would I delete it?
Does the master page have its own viewstate? Would I be able to make sure none of items on my master page are using the viewstate?
I am writing a search results page for an airline booking system. I have Next/Previous buttons to view flights for the next or previous days. The way i have done my results grid is that i use an HtmlTable and dynamically add rows, cells and controls into the cells. This gives ultimate flexibility given that we can add any control type we want and have it function as it does everywhere else in the system. As you should be aware - i must recreate these controls each time the page is reloaded (in the page_init event) since asp does not handle this automatically.
When they go next/previous it refreshes the flight data and re-populates the grids. If they select a flight in the return grid (by checking the RadioButton), and go next on the FIRST leg grid, the selection of the return leg stays the same after the postback - which is great. But the problem is, if the flight they selected on the return leg is no longer available it will not create the control and i get the following error;
"Microsoft JScript runtime error: Sys.WebForms.PageRequestManagerServerErrorException: 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."
Is there any way to tell asp.net that if you do not find the control anymore, simply ignore it rather than throwing the error? The nature of this design is that there potentioally WILL be a different layout after the page is posted back.
SelectedIndexChanged event doesn't fire for the first item of the DropDownList. For any other item SelectedIndexChanged fires, but not for the first one.Could someone, please, explain what kind of magic is it?(I use Visual Studio 2008)
i have an form with an button and some input controls. some time due to input problem i may get error after that if i refreshed the page then that time the button click event has fired, how to avoid this kind of bad event fire.
I have created a matser page with a two radio buttons, text box and a button. Whenever user sets some values to these control and clicks the button, i will navigating him from one content page to another based on the data he has entered. The problem is after the content page load, the values selected/given in the controls(radio button, text box) are getting cleared.
I have a page that loads a usercontrol dynamically. Depended on the user's actions, this control may be unloaded in Page_PreRender and a different control may be loaded instead. I am attempting to use the solution outlined by Mark DotNet Evans in this post: http://forums.asp.net/p/1491790/3814320.aspx
This all works great, except if the user clicks the refresh button in the browser just after the change of usercontrol. Then, I get an error
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. ...
I assume the error is caused by the browser re-posting the request with the old viewstate that matched the control tree when the page was loaded, but no longer does. How can I prevent getting an error when the user reloads the page?
I have a simple search page with a drop down list that I would like the value to persist on refresh..basically the user will select their location from the dropdownlist and this will be used to populate a gridview. After this the page is set to refresh at a set interval and use the same location data initially selected by the user. However the initial selection is lost each time the page refreshes.
p.s system is to old for ajax!
<meta http-equiv="Refresh" content="300" /> <script runat="server"> Dim connectionString As String = ConfigurationManager.ConnectionStrings("****").ConnectionString Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) If Not IsPostBack Then Dim conn As SqlConnection conn = New SqlConnection(connectionString) Dim Locationcommandtext As String Locationcommandtext = "SELECT * FROM [Location] ORDER BY [Location]" Dim loccomm As SqlCommand loccomm = New SqlCommand(Locationcommandtext, conn) Dim reader As SqlDataReader Try conn.Open() reader = loccomm.ExecuteReader() Locations.DataSource = reader Locations.DataValueField = "LocationID" Locations.DataTextField = "Location" Locations.DataBind() Catch ex As SqlException Response.Write("SQL Error: " & ex.ToString()) Finally conn.Close() End Try Else '"Viewstate should kick in here" End If End Sub </script>
I have a script that loads diferent photo in same div on masterpage for diferent pages.
So my question is how can I know what page is currently loaded so I can use something like this:
onpageload... Dim pageID as String pageID = ????????? If pageID = "default1.aspx" Then image1.ImageUrl = "~/zagreb.jpg" ElseIf pageID = "default2.aspx" Then image1.ImageUrl = "~/split.jpg" End If
maybe I can put some kind of ID on every page but how?
HTTPresponse does not help to much becouse links looks diferent every time (default.aspx?sasa , default.aspx876786 .....)
I am using a FormView and on insert I want it to be redirected to another page and take the ID of the FormView which I have just inserted so I can have page b load with the date from page a that I have just inserted
Here is my scenario.In default.aspx page user selects the country, state, city from drop down list, and store them in cache for further use. but when other user open the web site from other computer it shows the same country, state, and city selected by user 1. Is there any problem related to cache? I have stored data as following.
cache["ctryID"] = ctryID;
cache["stateID"]= stateID;
cache["cityID"]= cityID;
I want to show default country, state , city at page load of default.aspx
I want to know that when we create custom controls, then is there State Management through ViewState done automatically or we have to handle it explicitely ?Since i have created Custom Controls that is behaving as if it is not maintaining its state on PostBack.
I'm using the beta version of Visual Studio 2010. I'm running my ASP.NET 4.0 website through the debugger. Whenever there is a page load (e.g. clicking on a link, a postback) the session is ended and a new session is created. This wipes out all the session variables and makes debugging impossible. How to get session variables to persist across page loads?
Is this problem unique to running ASP.NET in a test environment or unique to the beta 2 version of VS 2010?
I make a user control with DataList to expose pagining . I choose to use ViewState to save the state of pagining (TotalItems , CurentPage etc) , but it seems the view state of the parent page is not "synchronized" with the one from user control . It's basically the same situation like the example :
I have a dummy user control :
"<%@ Control Language="C#" AutoEventWireup="true" CodeFile="WebUserControl.ascx.cs" Inherits="WebUserControl" %>"
I start with a blank ASP.NET page where I disable ViewState for the whole page with EnableViewState=False and even ViewStateMode=Disabled.keep adding various controls to the page -- Label, Table, Calendar, TextBox, DropDownList.Everything looks good, i.e. my __VIEWSTATE tag fluctuates between 24 and 28 characters.As soon as I add a single RadioButton (or CheckBox), the __VIEWSTATE shoots up to 130 characters. And it keeps growing by over 100 characters every time I add another RadioButton.
I have a code like this in the Me.LoadComplete event.
[Code]....
Now I would like to set this viewstate("data") = nothing on a certain button click in a user control (.ascx) in this page but it doesnt clear the viewstate. What am I doing wrong? In the onClick even of the button in the .ascx I write Me.viewstate("data") = Nothing
ive a simple webform where a checkbox enable the send button, this check is used for disclaimer agreement and has autopostback set to true; when a user insert all the required data to register, including his password and the check is clicked the password fields are reset to null because of the postback, i need to leave the check at the bottom of my module and consecuently the users most likely select it as last control.