AJAX :: Reference Not Set To An Instance Of An Object?
Feb 19, 2011
I m Creating a Website Student Management And During Student Registration Getting this Error' Object reference not set to an instance of an object.'I m using LINQ Please Gv its Solution ASAP.my Code is :
protected void Button1_Click(object sender, EventArgs e)
{
{
StudentDataContext db = new StudentDataContext();
int flag = db.prcInsertStudent((Guid)Membership.GetUser(txtFirstName.Text).ProviderUserKey,txtRegNo.Text.Trim().ToString(), txtFirstName.Text.Trim().ToString(),
[code]...
in my default.aspx page i have a dropdown List and a textbox with a submit button below that there are 2 listbox... and the dropdown list holds the names of the listbox
my logic here is to select an item from the dropdown list and put some text in the text box and submit the form which will add an item to the listbox selected.. but when i do this i get an error saying Object reference not set to an instance of an object. i tried to figure out the problem and found that when i remove the reference to the Site Master Page it works fine and when i undo and apply my reference back to the Site Master Page i get the same error.
I have a list of items on my page. There is a button in each row to edit that record. Record is being edited in jquery modal window. So I make an asynchronous call to server to display detail information about record without full page refresh.
User fills in data about that record and submits. If everything is ok, user is redirected back to page. But if validation fails I want to display that entry form again with errors.
If this call is done synchronously, users gets back form with filled data and errors, but without styles and javascript (because they are referenced from mail page) - that is ok
So I just wanted to refresh that modal dialog with asynchronous call. The problem is that Html.DropDownList or Html.TextBox extension methods fail with null reference exception. I have checked that real data are passed in as second parameter.
So I don`t understand where that null reference exception occurs, or what can I do?
The same call works if it is synchronous (Html.BeginForm) but fails if it is asynchronous (Ajax.BeginForm)
http://www.somepage.com/main.aspx. In this page, when I click on a link it takes me to a page http://www.somepage.com/cental.aspx?cid=200. So in the cental.aspx.cs page I did the following in the page load:
if(request.querystring["comp"].tostring() != null) { //do some thing [code].....
So I got an error like: object reference not set to an instance of reference.My problem is, I am using the same page. So when I go from some page, I will have "comp". but other times not. So when there is no "comp", how do I handle it in request.querystring?
In the VS2005 environment, when I test my session to make sure the page redirects to the main page (itself) if the session is null, it works. There is no error.
The function I use for this is:
[code]....
However, when it is in the production environment in IIS 6.0, when the session has timed out, and I then do a postback by doing some slider control, I see the page reload but immediately thereafter, it throws a Server Error exception of : Object reference not set to an instance of object.
however, why is it that the Slider1_TextChanged event fired even even after during page_load, the page was told to do a response.direct ?? shouldn't the entire page have gone through a full-page refresh life cycle ? why did it continue on to attempt to raise the Slider1_TextChanged event?
this works fine on my local site but as soon as i upload the site to my live server i get stem.NullReferenceException: Object reference not set to an instance of an object
on the first line of this:
if (!Page.User.Identity.IsAuthenticated) { pnlSignIn.Visible = true; pnlSignOut.Visible = false; }
can you please help me to brainstorm the possible causes of this error. I've got a paged repeater with localisation bound programitcally to an sqldatasource using a stored proc. I can post code if needs be but it's rather long. I'm looking for typical causes of this error + will make note for future reference!
erver Error in '/WebSite4' Application.
Object reference not set to an instance of an object. Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:
[Code]....
Line 233:Line 234: Repeater1.DataSource = PagedResultsLine 235: Repeater1.DataBind()Line 236: doPaging()Line 237: End Sub
I'm new to programming in ASP.NET, but I'm making my way through Wrox's Beginning ASP.NET 3.5 in C# and VB.NET.
I'm at a section where I'm creating a BasePage. I successfully created a BasePage by creating a new class file in my App_Code folder called BasePage.cs with the following code:
[Code]....
If I run that code everything works out fine. The page loads and all is well. But, if I try to do the same thing to a page that uses my MasterPage.master file, I get the following error:
Object reference not set to an instance of an object.
Description:
An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Why is that? In the example code from the book (that also uses a MasterPage.master file), everything excutes and runs just fine. But in my test, I get the above error. I've tried comparing my pages to the books included source pages, but I can't find any differences.
I have a website written in C# that was running fine on one server. We moved it to another server and have a couple issues. I am mainly a VB.NET coder but can do a few things in C#. This is not a project - it is a website and can open it in VS2008 no problem. This is an admin site for the whole website where the user can add customer comments, etc. When logging in, it works fine. I can go to one of the admin pages after logging in and works. If I go to two other different pages, I get this error:
Object reference not set to an instance of an object.
[Code]....
It turns out this is in the main.master page and it is used by the other pages that load fine. The ApplicationTitle variable is set right in the web.config file and like I said, it shows on the other pages.
My question is why would this code work fine for some pages and not two others? All of these admin pages are under a folder called Admin and the web.config file is in the root folder of the website. Its almost like these two pages cannot see the web.config file in the root folder? Why would that be if thats the case?
We have an applicaiton that was converted to the new framework using the wizard in Visual Studio 2008. When we install the applicaiton in production and change the iis settings to use the 2.0 framework we start to see these errors in the event viewer on the web servers. We are using SQL Server Session State and have 3 web servers in a load balancer. Object reference not set to an instance of an object.</Message><StackTrace> at System.Web.SessionState.SessionStateModule.PollLockedSessionCallback...
I have a webservice, it has few webmethods. when i create a client proxy and invoke the methods to check its response, i am getting this error. Can someone tell me what things can i check to know the cause of this? The error is not saying much hence blocked on this.
On Edit Click, the DropDownList in the GridView brings the previously selected value.On Update Click, the error is: "System.FormatException: Input string was not in a correct format."
ddlRegionNavn.DataTextField = "RegionNavn"; ddlRegionNavn.DataValueField = "RegionID"; // from RegionNavn to RegionID
On Edit Click, the DropDownList values in the GridView is not firing and the following error shows.Object reference not set to an instance of an object. How to implement the code when having a value of type Int ?
private void FillDetails(string pId, out string Name, out string Address)
[code]....
I have method called Filldetails(),This method uses stored procedure to retrieve information for product name and address based on productid passed from productdetails table.I am working on globalization project.We have this product information for US country but there is no product information for germany country.So dataset is empty for germany.As result I am getting error object reference not set to an instance of the object.
I have just recently converted my VB code to C# and now having this error when I try to add an item to my listbox, and the value is coming from the item page. I get the error at this segement:
lstboxCart.Items.Add(cartItem.Display());
My listbox is supposed to add the product's name, quantity, and price onto one row.
Here's what I have so far:
[code]...
[Code]....
[Code]....
My guess is that the source of the problem could be in the foreach loop from my cart class, shouldn't I be using that for arrays only? If I need to post any markup code or any other class, let me know.
I have the following code in my form load that loads the reports and assigns it to crystalreportviewer control. If Not IsPostBack Then
[Code]....
Following is the ApplyCRLogin Class
[Code]....
Now when I run the site it prompts me for the parameters and when I enter them and click on OK, I get the following error. "Object reference not set to an instance of an object." But the strange thing is if I comment the "If Not IsPostBack Then" condition, my report works fine. The problem is even when I want to go to the next page in report, the code get executed again and this takes time. Is there any other way to fix this?
Object reference not set to an instance of an object.
Description: An unhandled exception occurred during the execution of the current web request. review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.
Source Error:
Line 21: { Line 22: base.OnInit(e); Line 23: _ContentTemplate.InstantiateIn(BodyControlSpace); Line 24: } Line 25:
What is wrong with this code? The error is Object reference not set to an instance of an object.
I have the below code in my class, then on the login page i need the GUID so i can perform a lookup in one of our custom tables. But then the error above pops up before the page even loads at the line Guid guid = (Guid)userInfo.ProviderUserKey;
