Web Forms :: How To Reference A Object On Another Aspx Page
Oct 26, 2010
I have a basic ASP.NET (4.0) web site (in VS2010)
I have a few aspx forms with in it..
on default.aspx I have a aspxbutton1
on report.aspx I have a aspxlabel
All I need to know is HOW do I reverence the label from the default page and visa versa..
In the web world things are not the same.. This is just an example .. to prove the point.. but I am trying to copy the settings from one object on page 1 to an object on page2.
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'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.
but I run page below error happen.Object reference not set to an instance of an object.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 91: if (_dr["storetype"].ToString().Trim() == "دارای محصول")Line 92: { Line 93: RBLType.Items.FindByText("دارای محصول").Selected = true;Line 94: } Line 95: else {
i have create dynamic menu control , i have master page and login page , once the user login , i want to show the dynamic menu in my master page. below i try to call masterpage control in my child page ,but i throughs the error
Object reference not set to an instance of an object. my master page code public partial class MasterPage : System.Web.UI.MasterPage { protected void Page_Load(object sender, EventArgs e) { } public string MyProperty { set { // lblUser.Text = value; lblUser.Text = value; // here i got the error } } }
My child page code
protected void btnwork_Click(object sender, EventArgs e) { ((MasterPage)this.Master).MyProperty = "Text changed from Sub Page"; }
I am using grid view as mentioned below, it is giving me error "object reference not set", but if comment allowpaging and pagesize lines, it works. let me know whats wrong I am doing?
Given an instance of a control SomeControl that is in a some file (could be a usercontrol/ascx, or an aspx) how can I get a reference to the class to which it belongs?
In a usercontrol, SomeControl.NamingContainer seems to be reliable.
In a page that inherits from a MasterPage, this will return a reference to the ContentPlaceHolder, not the actual class that defines the aspx. What I would want in that case is SomeControl.Page
Parent will return the parent control in the heirarchy so isn't much use.
Is there any method for getting this directly regardless of what kind of thing it is?
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; }
I am developing a usercontrol, in this case a toolbar. Some of the buttons on the toolbar will interact with other objects on the page which are not part of the toolbar. (In this case a map) So the toolbar code behind wants to say something like this:
[code]....
My problem is that MyMap does not exist in the design environment of the usercontrol and therefore produces an error when it is referenced. So my question is, How is this typically handled? Can the usercontrol reference another control that does not exist within itself?
I am trying to develop logic to add dynamic controls to page via class method. So I want to know how can we access the ASP.Net Page object reference in class method.
I'm using IIS 6 on a Windows 2003 Server and I am trying to get an MVC2 project installed on that machine. I am having nightmare-ish problems doing so!I've looked up TONS of references on what to do, and not 1 single one works. (They work for MVC1 projects, as I have a few of those running already using said solutions).
I have tried it on 2 of my dev servers, and both get the same result. The closest I can get to a served page is an error page "Object reference not set to an instance of an object", however, the page has try/catch blocks that are being ignored, so I dont think its running the code on the controller, I think it's saying that the controller is the error. (For the reference, the error in question is directed at the HomeController.cs file).
What I've tried:
Wildcard mapping Changing routes to {controller}.mvc Changing routes to {controller}.aspx Adding the .mvc extension to IIS Modifying routes in Global.asax
There's a LOT of code in this project so far, so I will only post the first page(s) that should get served:
MASTER PAGE:
<div class="page"> <div id="header"> [code]....
I did not list the CreateUserSecurity method, but all it does it call the DB using the Username and returns the record in the database that matches the username.
EDIT: Added code and what I've tried so far (as requested).
I have published a aspx website in IIS 5.1. My second page refers to a .dll file of a vb6 program.My backend program is written in c#.At first when I published i couldnt load my second page as I got an error saying that I have to register external com objects....
so I registered the dll file in my root directory using "regsvr32 ". Now after registering im able to access that page, but the buttons are not responding. When I click the buttons on the page the refer to functions in that dll. But its waiting for localhost to respond for a long time and im not getting the results.
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?
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 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?
I have a page that calls on an asmx within the project (for some ajax stuff). Within that asmx I'm calculating a value and returning it to be output to the screen.
However I need to do a recalculation that includes summing this value with a few others. The function that performs the calculation is in a UserControl on the page.
How do I get a reference to the page object so I can use FindControl to get an instance of the user control so I can call that calcuation function?
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.
