Web Forms :: FindControl Returns Null When Change Browser Language?
Jul 6, 2010
Like the title says, when I try to get a control (HiddenField) using this.Parent.FindControl it returns an exception. Curiosly this only happens when I change the browser language to Italian, English but not Spanish (I'm from Argentina so everything in my computer is spanish).
Why method FindControl() returns null on FormView until call DataBind(). After that it returns everything correctly? What workaround are there? Call DataBind() before first call of FindControl() ?
I've been working for a long time with GridViews and DetailsViews, but yesterday I've come across a new scenario, which I quite do not understand.
I have a GridView with ImageButton (CommandName="Insert") which will change the mode of the DetailsView to Insert. Afterwards I'll look for a DropDownList inside that DetailsView and add some items dynamically. Works fine, but one first the first time I press that ImageButton. If I click on "Cancel" in the DetailsView and press the ImageButton again, the .FindControl() Method returns null.
I've created this sample: (To make it run in your Visual Studio, just bind a DataSource to the DetailsView, otherwise it will not be rendered)
I have also tried using a ItemTemplate, and not a InsertItemTemplate, but this results in the same. After using the ChangeMode-Method the DetailsView.CurrentMode == InsertMode. The only thing I can think of is, that the markup is already generated for the ItemTemplate and changing the Mode to InsertMode can't affect the rendered markup, or something like this.
I have a UserControl that has some controls inside. I want to refer those controls after, in another postback. But when I try to get them the Controls property of my controls returns null. I'm working on vs2008.
Here is the thing. I have an aspx page with NO master page. I have two resource files with the same name (and specifying the language) in the App_LocalResources folder. If I do something like text="<%$ Resources:lblUser %> works fine. What I do to test it is change the browser's selected language.
But, if I do the same in a MasterPage or in a Page that is inside a MasterPage... when changing the Browser's language and refreshing... I'm still getting the default language...
I've been reading some threads about this but the situation was a little bit different.
I have created a web application and generated local resources. Its working when user select language from browser. But what i want is, when user select language from dropdown list, i want to change the pages according to selected language. i can save user selected language in a session. then how should I change/assign local resource file to web page?
I developed a page in VWD 2008 and it works perfectly locally, but when I deployed it on the server every Page.FindControl() call is causing the NullReference Exception "Object reference not set to an instance of an object. " Can anyone help me out? Code is below
I've a gridview with one textbox column and 1 label.
Based on language selection im changing master page and gridview will be bind with data based on language from database . When change the language the labels will be binding with data based on language . but textbox value is not binding properly.i.e;for example i've 2 languages English and Arabic . First i've logged with English Language gridview is binding correctly after chnage language to Arabic the textbox value is not binding is displaying with data previously whatever binded with english language. Other than this textbox remaining label data bindind with data in arabic language.
I have a gridview. In the rowupdating event, the txtbox returns null. I have enabled viewstate for the gridview. But still it does not work. I have made this in Kentico.
Since I am not using a DataSourceId at the markup I am having to create my own Sorting handler. I found a sample on MSDN but the variable 'dataTable' always returns null why?
I've run into an issue where calling SiteMap.CurrentNode returns null when it really shouldn't be. I'm using SiteMap.CurrentNode to highlight certain buttons on the page and generate a sub navigation bar (through SiteMap.CurrentNode.ChildNodes).
Now this works until I attempt to get to my pages of which are generated by a dynamic provider. For some reason whenever I attempt this on my Projects page SiteMap.CurrentNode returns null. Overall this is a bad situation for my program because then I cant generate my sub-navigation bar.
I was hoping someone here might be able to figure out the fault in my Sitemap or provider so that I can do a basic tutorial to others who are attempting the same thing since I haven't seen a tutorial that implements a provider in the manner that I have.
Web.SiteMap:
<siteMap xmlns="http://schemas.microsoft.com/AspNet/SiteMap-File-1.0" > <siteMapNode url="~/Default.aspx" title="Home" description="Home page where updates and other information can be found"> <siteMapNode provider="ProjectProvider" /> <siteMapNode url="~/Contact/Default.aspx" title="Contacts" description="Contacts" /> </siteMapNode>.......
Provider:
Implements the following methods and all of them do not return Null (I checked via debug): - RootNode - GetRootNodeCore - Initialize - Clear - BuildSiteMap
I have a treeView on my main page. While the page is postback the method TreeView.FindNode works fine. But when i return to main page from another, and loading ValuePath from session it returns null.
here is my treeView [Code]....
Code behind to save values in session on Page_Load:
[Code]....
Code behind to select TreeNode after return from other page on PageLoad
Our application uses the Enterprise Library's PropertyProxyValidator class to validate user input (v4.1 - Oct 2008). On occassion, the code will raise an exception saying the source type cannot be found. This error persists until the application pools recycle at night, at which point everything works again. It tends to only affect one of the web front ends at a time (there are two). I tracked down where the exception was being raised, and this is the section of code:
[Code]....
(As you can see, the value for this.SourceTypeName is shown in the exception and I've checked that it matches exactly.)
We have never been able to reproduce this exception and at this point don't have any ideas left as far as causes. For a while, my suspicion was that it was related to the Temporary ASP.NET Files folder. The last time the error occurred, I copied that folder from both web front ends. Then the next day when things were back to normal, I copied the folders. When I did a directory and file comparision of the affected web front end, I found no differences.
Our application is essentially user controls hosted in web parts on SharePoint (they don't do anything with SharePoint - in fact, for a while, we were developing the controls on ASPX pages). There are two servers in the farm, both with Windows Server 2003 R2 Standard x64, IIS 6, and .NET v3.5. This issue doesn't strike me as a problem with Enterprise Library or SharePoint, hence why I've posted here, but more so with assembly loading.
Any ideas for causes would be greatly appreciated. I could also use suggestions on tools I could use to try and debug this when happens again (it happens 2-3 times a month) in production.
I'm not sure what is the best way to create website that allows user to change its language. The website is really small, it has couple of pages (Default.aspx, Location.aspx, Catalogue.aspx and Info.aspx), but I'm not sure how to change the language of the content. User can change the language by clicking on one of the four image buttons which then add "lang" query string to the url, but whenever page reloads it keeps adding more and more "lang" querystrings.
I have a very strange issue where SelectionList always returns NULL when i try check its Selected Item/Value. I Googled a bit and I found out that when i click the submit button, the page is being refreshed and the SelectionList is being data bound again so it will revert back to its original behavior.
Then i tried enclosing the binding code in the Page_Load event in a !IsPostBack but still when i try to access the Selected property it is null and an exception is thrown.
My code goes something like this... (the braces are not matched properly)
Im dynamically creating several dropdowns onclick of a button... but the dropdown returns null when im trying to get the values on submitting the form... i read tat during postback all dynamically created controls will be lost... s there a way to register the controls... i want to access the item selected in the dropdown .... expecting a positive reply...