I have been using session variables in my asp.net application for passing the next property:
[DefaultValue(true)]
public bool IsModificationMode
{
get
{
return (bool)Session["ModificationMode"];
}
set { Session["ModificationMode"] = value; }
}
In the PageLoad, I set it's value.
Now after the Postback, I am losing it's value having a a NullReferenceException
In a page I have a link; clicking on it opens a dialog and sets a textbox value for that dialog.
However, once I click on submit in that dialog, the textbox value is null.
Link:
<a href="#" onclick="javascript:expand('https://me.yahoo.com');
jQuery('#openiddialog').dialog('open'); return false;">
<img id="yahoo" class="spacehw" src="/Content/Images/spacer.gif" /></a>
[Code].....
I have an upload control (csv file) of which I use the stream to retrieve data in a datatable that I then bind to a datagrid, sitting in a repeater control.I have to bind more than one record to the repeater, therefore I need to find a way of storing the stream for each binding, so that I can bind it to the datagrid again, via itemdatabound event of repeater.
I have tried storing the stream in the repeater's datatable but on each postback, the content of the stream gets lost. The stream still exists, but its length is set to 0.I have tried storing it in a session object, but again it is reset to 0.
I have tried using viewstate but I get a xmlserialization error. Saying IXmlSerialization is not implemented.I am desperate to find a work around as I am feeling the pressure at work.
I have a ascx page where I am using a hidden field to store the value of a the drop down box as it is generated using a google address finder. My problem is that when I try to store the value directly in the hidden field :
hfDdlVerifyID.Value = ddlVerifySS.SelectedValue;
in the event of a button click, the value is stored but on postback is lost again. Whereas, if i try to use Scriptmanager to do it, nothing is stored.
getBuild.AppendLine("$get('" + hfDdlVerifyID.ClientID + "').value = $get('" + ddlVerifySS.ClientID + ").value;");
ScriptManager.RegisterClientScriptBlock(this.Page, this.GetType(), "storeHidden", getBuild.ToString(), true);
// Page.ClientScript.RegisterClientScriptBlock(this.GetType(), "storeHidden", getBuild.ToString(), true);
string test = hfDdlVerifyID.Value.ToString();
[Code].....
I have a form with a update panel. This posts the form and validates it. Returning a errorMessage string of any invalid field such as "Field xyz is a required field, Field abc needs to be a quantity"
When I enter incorrect date it posts back fine and displays the text in a div at the bottom of the page which the update panel is aimed at to update. (and only this it should be changing)
This works but the second time I hit say (say i enter invalid data twice) the Complete form will disappear leaving me with just the banner of the site and the error message that is returned.
Ive tried commenting out the entire of the code post back so that the button doesn't actually do anything but it still has the same problem(of course this time it wouldnt have a error message created)
So i can only think it is something to do with the updatepanel itself and how it works but i have been staring at this for ages and have no more ideas!
I am in beginner level on developing web pages. I was coding on desktop applications and as you know it is easy to say that web applications are extremely different than desktop applications.
I wonder why data are lost between postbacks.???? And what is the best way not to lose the data belonging to a specific control (especially gridview). Session or viewstate or anything else?
Never had this happen before. I just upgraded my site from 3.5 to 4.0. Here's the scenario:
1.) I have a literal on a web form, in an UpdatePanel.
2.) On PostBack, the Literal's "Text" property loses it's value. The ViewState is enabled throughout the page. Further, I changed the Literal to a label and it also has this problem. The TextBox's appear to keep their values.
3.) If I remove all of the Ajax controls (which currently is just the UpdatePanel and the ScriptManager) then the Literal control keeps it's value through PostBacks.
4.) There is no client side JavaScript where I'm manually changing the values of these controls. They are only editted in the server side events.
I have read that setting the AutomaticDataBind property in the web.config could remedy this but I can't find any documentation on it and I don't know where to put it in the web.config to even try it.
I am using the AJAX Contol Toolkit and 4 CascadingDropDown extenders with an ODBC connection in a Web Service. The original load of values in each level works great. I then use these values to set the create the SQL for the SelectCommand for a Gridview.
The problem I am having is that when I submit the page to perform the search, the first 2 dropdowns repopulate and set the selected index accordingly, but the 3rd dropdown does not retain its selected value. It does populate with the values, but the selected value does not get set.
The correct values are available for the SelectCommand which returns the correct values.
Private Sub UpdateOffensiveStats()
Repeater losing data on postback
I thought about saving all sessions variables to hiddens and then resaving those values back into session after I changed the web config..but there has GOT to be another way.
View 1 RepliesI have two radio buttons that are disabled with javascript when the page loads. RadioButton1 is checked by default. When I click the button to do a postback, the RadioButton1 is no longer checked.
Here's my code sample. The code behind is empty.
<asp:RadioButton ID="RadioButton1" runat="server" GroupName="group" Checked="true"/>
<asp:RadioButton ID="RadioButton2" runat="server" GroupName="group" />
<asp:Button ID="Button1" runat="server" Text="Button"></asp:Button>
<script type="text/javascript">
window.onload = function () {
var RadioButton1 = document.getElementById('<%= RadioButton1.ClientID %>');
var RadioButton2 = document.getElementById('<%= RadioButton2.ClientID %>');
RadioButton1.disabled = true;
RadioButton2.disabled = true;
};
</script>
I have a simple asp:RadioButtonList within a form tag but for some reason it isn't keeping it's value on postback
Here's what I've got
[code]....
I am creating a ASP.Net server control to manage locations. The control is a composite control containing several text-boxes, labels, and a link button. I use the AJAX Control Toolkit to provide a modal popup which contains a Bing map. All the Javascript is in its own file and used as an embedded web resource.
The link button is what opens the modal popup. It also needs to call a Javascript function that initializes the Bing map (onclick = "GetMap();"). There are instances when this server control is placed within an Update Panel (and there is no way to avoid this). When in an Update Panel the link button loses its onclick event. I understand that this is because during an async postback the portion of the DOM that defines the content of the Update Panel is thrown out and reinitialized, resulting in the event breaking. When the control is not in an Update Panel everything works as intended.
I have tried registering events on Page.Load and Page.Init, like so:
[Code]....
I have also tried flat out writing the function call to the page:
[Code]....
I have put breakpoints on the lines inside each delegate and they do not get hit. I am not aware of any special way to register events of a composite control's child control or the Page.Load/Page.Init events when being done inside a server control. Is there some special way to register these events? (Note: Both those code blocks above are in my CreateChildControls() method)
Below is the GetMap() Javascript function. As you can see it is pretty straight forward.
[Code]....
i have a global field called hotelId. i then have this piece of code that gets a value from gridview row:
[Code]....
the local variable is assigned to my global one, which gets passed to my method along with other variables. while stepping through i can see the value is set, but when i hit the submit button variabl is passed to another method except my hoteId. it gets lost...
I am building a composite server control that currently only has a TextBox and a DropDownList. Here is the code in all its foetal glory:
[Code]....
The control appears to work correctly across postbacks, that is until declarative values are set, e.g.:
<squee:Address runat="server" ID="a" Street="123 Fake St" State="VIC" />
After this, the text box continues to work correctly, but the _state member does not pick up the posted back values and instead just sticks to the declared value. I've checked the raw posted values in the Request object, and the new value for the list's UniqueID is there, but _state doesn't pick it up.
I have a textbox that uses TextboxWaterMarkExtender and jquery-ui's datepicker plugin.Upon postback, my textbox is losing the value selected from jquery datepicker.Below is the sample code to see the behavior. Is there anyway I can make my textbox to retain selected value on postback?One thing to note is, if I use jquery watermark plugin, it does postback the value. But for certain reasons, I think I plan to use AjaxControlToolkit.
[Code]....
I've got some ASP pages where the session variable values get blown away BEFORE the session times out. I can't understand it. For example: if a user logs into my ASP app using his password which is stored in a session variable, it will be fully accessible for a few minutes and then all of a sudden.....Wham session variable with password value is gone. And the session timeout is far from expired. The session variable is not being touched in any way after it gets initialized with a value.
View 3 RepliesI am facing a very strange issue. I get an error Object Reference Not set to instance of object on the server while the code runs fine on my dev machine. The strange part is the line number where the code is throwing error (as appears in the Stack trace)
DemoUser demoUser = new DemoUser();
if (!Request.QueryString.AllKeys.Contains("name"))
{
playerName = usr.NinjaName;
demoUser.Email = usr.UserEmail;
demoUser.UserPicture = usr.UserPicture;
}
else
{
playerName = Request.QueryString["name"];
demoUser.Email = String.Empty;
demoUser.UserPicture = "http://graph.facebook.com/1/picture";
}
demoUser.EntryDateTime = DateTime.Now;
demoUser.Name = playerName;
Session["DemoUser"] = demoUser;
imgPlayer.ImageUrl = demoUser.UserPicture; // This is throwing error.
If that line is throwing error then the demoUser object is getting lost when I assign it to Session. Is that right?
This has been a nagging issue for some time, but very sporadic and difficult to isolate.
From time to time, browsers that have authenticated on a web application, have been open for a while, have logged in and out of the same web application multiple times, have multiple tabs, are pretty much any browser (Chrome, IE, Firefox, Safari), and seemingly at random, lose their ability to retain an AuthCookie after being set and followed by a redirect. Closing the browser and starting a new session resolves the issue, as does opening up a different browser and attempting to authenticate.
Our team uses forms authentication for all of our websites and web application. This is a pretty typical setup where a login form is displayed, the user enters credentials and a cookie is set on the click event of the postback, then a redirect occurs to the same page where the cookie is then referenced and used to complete authentication.
In this situation
FormsAuthentication.FormsCookieName = ".WebAuth"
Within Event:
FormsAuthenticationTicket authTicket = new FormsAuthenticationTicket(1, Username, DateTime.Now, DateTime.Now.AddMinutes(SessionTimeout), false, Username); HttpCookie faCookie = new HttpCookie(FormsAuthentication.FormsCookieName, FormsAuthentication.Encrypt(authTicket));
Response.Cookies.Add(faCookie);
Response.Redirect(Request.RawUrl, true);
After the redirect, on PreInit:
HttpCookie authCookie = Request.Cookies[cookieName];
At this point, the authCookie variable is typically not null, but in these isolated circumstances that I've outlined above, the cookie comes back null after the redirect.
This happens very randomly, sometimes weeks before affecting one of our developers. As I said, restarting the browser resolves the issue.
Today I had it happen on our dev server while using Chrome. I had logged into the application, allowed the application to session timeout, and then attempted to login again. The attempted login then failed to set the cookie. I remotely attached Visual Studio to the process on the server to begin debugging. The entire time I could step through my code, even deploy new code versions to the server with updates, restart the app, restart IIS on the server, attach and reattach to the project, and the issue persisted in Chrome. In Firefox, I was able to authenticate without issue.
From Chrome, the login would validate, attempt to set a Response Cookie as outlined above. Prior to redirect, I could see the properly set Response Cookie, as well as its counterpart in the Request Cookies. However, on each redirect after a seemingly successful login, the Response and Request Cookie are gone.
I enabled Trace on the application to view the cookie collection:
There is a .WebAuth in the Request Cookies Collection, as well as ASP.NET_SessionId and several ASPSESSIONIDxxxxxxxx, but when the page loads, only the ASP.NET_SessionId and ASPSESSIONIDxxxxxxxx cookies are available in the Request.Cookies scope, no sign of the .WebAuth. However, in the page's Trace information after render, there multiple .WebAuth cookies listed, it is just that the page seems to have no access to them.
Primarily, on a working version after authentication there is both a .WebAuth Response and Request Cookie in the page's Trace info. But on a non functioning browser window, the Response Cookie is absent.
Has anyone else had any experience with this? It is such a nagging issue, and so sporadic, but I would love to be able to resolve it. My concern is that it may be affecting users and we would have no knowledge since the description of the issue is so convoluted.
I have a asp.net application where I am saving off into session the user privilege information. From a grid I am bring up a new window by using the window.open. It seems that it is whiping out the values in session. A temporary bandaid I have placed on it is to recall the database if the value is nothing to reset the user object. I have found all over the internet that this is an issue with the window.open in IE 7 and IE 8. Has anyone else run into this and able to actually fix it?
View 4 RepliesThere are a couple of user's experiences session variable loss after they've clicked a confirm button and their information is email via a relay hosting server. Below, I commented exactly where the session variables get lost.
What could be causing the session variable loss? So far, this only happens to a few users.
Part of the email that gets sent out:
[Code]....
Web config file:
[Code]....
I am using partially secured pages ( SSL). Now the problem is when I am switching between HTTPS and HTTP, I am losing my session. I tried storing session in Sql Server Database, its still not working. I am using just ONE web server and all pages are in single application.I am using Sql server 2008 ,IIS 7.0, C#.Net 3.5 I created a self signed test certificate to test my application.
I understand that I am losing my session because my urls are changing with https and http but there has to be someway to overcome this problem. I dont want to put unnecessary load on pages which do not have sensitive data by using https.
I have health monitoring enabled on a production system (asp.net webforms .net 4) and I see that there's a lot of errors being sent to me indicating that a session variable has been lost.(I am trying to attach something out of session state to a entity framework data context and get a "Value cannot be null, parameter n ame entity" error). So somehow the session variable now contains null and not an object. Interestingly we have the same application deployed on two separate servers - one DMZ server for external users and one internal server for internal users. Both of these applications on two different servers seem to have the same problem.
Health Monitoring is also monitoring lifetime events and I can see from this that we do not have something like IIS recycling, config changes, changes to bin folder, recompilations etc, occuring. I've read this page: [URL] I can confirm that it's not a Response.Redirect problem because that's not happening - this is an online application form - it puts an object in session state on page_load and there's a multiview - when "next" is pressed, the object comes out of session state, is attached to the data context, changes are made from the web form and the datacontext updated. So there's no response.redirect happening.
I can also confirm the details in "Update 1" and "Update 2" from that link are not relevant to me - there is only 1 worker process running in the application pool and the server name or web address do not contain underscores. I also persued the possibility of session timeouts occuring but they should be handled by other code which is running to detect session timeouts (see: [URL]) which I have tested over and over - Part of the problem is I just cannot reproduce this error myself.......................
OS: Windows 7
VS: VS 2010 Pro SP1 - IIS Express
I am debugging my project, the first page is a login page which I login and I can see from debug that the session is being set, after the redirect to the homepage the session seems to be lost and I am taken back to the login page.
If I run outside of VS on our sandbox or production server the login works fine. It only seems to be my machine w/ VS that does not like the sessions.
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.