I am declaring a list in my class, populating the list in page load and using the list in various methods in this class. But, I get this error at every instance where I use this list in the methods. Error: System.NullReferenceException: Object reference not set to an instance of an object.
ASP.NET Web-forms Javascript (jQuery for instance)
Case,To make it clearer let's give the Stackoverflow Users list as an example. This list can be manipulated at client-side. I can search, page and so forth. So obviously we would need to call jQuery.ajax to retrieve the HTML of each page given a search. Alright. Now this leaves me with the first question:
What is the best way to render the response for the jQuery.ajax at server-side? I can't use templates I suppose, so the most obvious solution I think is to create the HTML tags as server-controls and render them as the result of an ASHX request? Nice. That solved we have yet another problem:
When the user first enters the Authors List the first list page should already come from the server completely rendered alright? Of course we could render the first page as well as an ajax call but I don't think it's better. This time I CAN use templates to render the list but this template couldn't be reused in case 1. What do I do?
Now the final question: Now we have 2 rendering strategies: 1) Client and 2) Server. How do I reuse code for the 2 renderings?
When I get an Object Ref error, it can sometimes be a real pain to find out which variable is causing the error (when you can't debug). Is there a way for this error to throw the classname that isn't assigned?
I started my project in Asp.net MVC(c#) & SQL Server 2005.I want to implement Object Databases in my project. While searched in google i found "MongoDb" & db4o
I didn't have enough knowledge in Object Databases & which one best suited for SQL Server 2005.
good example/reference regarding Object Databases implementation in Asp.net MVC application
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?
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.
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 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?
I am trying to run the 15 minutes movies MVC application but I got 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.
I have 2 pages in my project (that are causing the problems). My default page has a FormView that for some reason will not let me access page events, such as buttons for instance, in code behind. They show up fine on page but are not visible in the page events drop down in code behind. We are using a work around for that.
The main issue now is that on my ViewTaxes.aspx page I need to get the values of some of the text boxes from the default page by Control Number, i.e. whatever record is being viewed on default page when you click the ViewTaxes link button, much more detailed information about that particular record is displayed on ViewTaxes. If on ViewTaxes I use a SELECT * statement I can access the ViewTaxes page when I click the button. We, of course, need to filter the data displayed by ControlNumber. When I add a WHERE clause to the DS on ViewTaxes page and click linkbutton on the default page I get an Object Reference error. This error seems to have something to do with a group of textboxes that are displayed via Session in codebehind. Values from default page being displayed in one section of ViewTaxes page. The error when thrown always points to Session("Owner1") = txtCust1.Text. If that code is removed then error will go to next Session variable, an so on.
I should also point out that both pages worked fine, no problems at all, using a test MySql table. We recently migrated the actual table that will be used from an Access database and replaced the test table. Can't find any spelling errors or anything of that nature. There are some Null fields in this database but it is set to allow Nulls.
Here I want when click on linkbutton it change text's color so I wrote below code:
protected void c(object sender, EventArgs e) { this.GetCustomersPageWiseMC(1, (sender as LinkButton).CommandArgument); BindDataListD(DLclassC, "classTI_documentry"); DataListItem item = (DataListItem)(sender as LinkButton).NamingContainer; foreach (DataListItem dlItems in DLclass.Items)
[Code] ....
For Linkbtnclass_Click it worked correctly and when I click on linkbutton it change color but for LinkbtnclassC_Click when I click on linkbutton it make this error:
Server Error in '/' 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:
Line 537: { Line 538: LinkButton lb1 = dlItems1.FindControl("Linkbtnclass1") as LinkButton; Line 539: lb1.ForeColor = ColorTranslator.FromHtml("#646464"); Line 540: } Line 541:
In manager.aspx page I have gridview that bind product information from database in this gridview I define linkbutton EDIT that when users click on it they go to Edit.aspx page and in this page users can see their product information and Edit them
In Edit.aspx page I use some textbox and dropdownlist and bind them from database
int data1 = Convert.ToInt32(Request.QueryString["Id"].ToString()); SqlCommand _cmd = new SqlCommand("viewProduct", _cn); _cmd.CommandType = CommandType.StoredProcedure; _cmd.Parameters.AddWithValue("@id", data1); _cn.Open(); SqlDataReader _dr = _cmd.ExecuteReader();
[Code] ....
When I click on EDIt linkbutton from gridview it go to Edit.aspx page and bind all data from database and ofcourse show data in Dropdownlist untill now every thing is ok
but when I change some Item in this page i.e Name of product when I changed and clicked on button to update table in database it update data in database but below error happen too
Server Error in '/behtop website' 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:
Line 79: Line 80: Line 81: DDL1.Items.FindByText(_dr["classification"].ToString()).Selected = true; Line 82: DDL2.Items.FindByText(_dr["subset"].ToString()).Selected = true; Line 83:
And when I back to manager.aspx and again click on Edit linkbutton to Edit that product it didn't load Edit.asp page and above error happen again...
This error happen just when I want edit product information in other time if I don't edit any thing edit.aspx page load successfully...