m a pretty new developer so I'm not well versed in common ASP.NET problems.As a test, my boss asked me to convert a (not very critical) ASP.NET site from 1.1 to 4.0. Well, it's not extremely difficult and things are going well so far. However, I've hit a small snag. I keep getting a NullReferenceException when I run this code
View 1 RepliesAs a test, my boss asked me to convert a (not very critical) ASP.NET site from 1.1 to 4.0. Well, it's not extremely difficult and things are going well so far. However, I've hit a small snag. I keep getting a NullReferenceException when I run this code:
[Code]...
When I am debugging an application in ASP.NET, after about ~5 minutes I get a NullRefEx coming from global.asax.cs regarding:
protected void Session_Start(Object sender, EventArgs e)
{
WindowsIdentity identity = null;
identity = (WindowsIdentity)(Context.User.Identity);
...
Context is Null at this point. I am a noob in ASP.NET with regards to Global.asax.cs. This code was written by another developer. EDIT: This is the code with HttpContext...
protected void Session_Start(Object sender, EventArgs e)
{
WindowsIdentity identity = null;
identity = (WindowsIdentity)(HttpContext.Current.User.Identity);
I'm using a third party control called an Accordion from Juice UI. Within that control, I have a table with labels.
VB.NET Code:
<juice:Accordion ID="accSwrlHddRepl" runat="server">
<juice:AccordionPanel runat="server" Title="HDD Information">
<PanelContent> <p> <table style="width: 99%;">
<tr> <td class="style2">
<asp:Label ID="Label2111111" runat="server" Text="Original HDD:"></asp:Label>
[Code] ....
I can't access the label directly, so I'm trying to use the FindControl method to get it and set it's text property.
VB.NET Code:
CType(Me.accSwrlHddRepl.FindControl("lblFirstHddReplacement"), System.Web.UI.WebControls.Label).Text = "string"
But I get a NullReferenceException. So I moved the label outside of the table and put it just inside the accordion. The same behavior occurs. Then I gave the accordion panel an ID and did FindControl there, but the same issue occurs.
I don't think I understand fully how ASP.NET does inheritance of controls.I have a user control, ucBase, which has an asp.net label in the ascx file. Code behind references the label and it works fine during run time if the control is not a parent for another user parent.
If I have another user control, ucChild, inheriting from ucBase, the label in ucBase's code is always null. ucChild has no controls in its ascx fileThe server controls (like the label) needs to be declared in the ascx file and not created programmatically.What needs to be done for ucBase to see its own controls when it's a parent user control?
I've got a web site that has a master page and that master page (mpMaster that has a user control ucControl1) which has a sub user control (ucControl2), this user control has a property which accepts a value. Now, I have a page that uses the master page
and on this page I have another user control (ucPageControl), I need to find a way of setting the value in ucControl2 from ucPageControl. Is this possible at all?
I am trying to assign user control from another user control ..first time its binding control successfully but when we refresh the data its giving error
saying "Object reference is not set an instance".
how to refresh data from another user control ...
My senerio below :
1 Aspx page
2. User control
calling usercontrol databinding method from aspx page but once it get refreshed ,not allowed to bind it again..
I'm attempting to create a simple menu user control just as outlined here.
The attached code results in an "Object reference not set to an instance of an object" error, but I can't figure out why.
<%@ Master Language="VB" CodeFile="MySite.master.vb" Inherits="MySite" %>
<%@ Register src="Controls/Menu.ascx" tagname="Menu" tagprefix="my" %>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">......
I have to access the parent form's controls inside an event handler method on my user control's code behind.
View 4 RepliesI have a web user control that represents a simple message box. It is used to display simple messages like "Item has been deleted", or "The item was saved successfully".
On the other hand, I have another web user control that represents the item in the form of an editable form (I made this a user control because this is used in two different pages). I want to embed an instance of the message box user control inside the editable form. I am writing this right after the @Control directive:
[Code]....
Instead of using @Register directives, I register the user controls in web.config and so far this has worked just fine.
With the above markup, the project compiles, but whenever I try to navigate to a page that contains this construct, I get an HttpParseException exception. Furthermore, Visual Studio states that the tack w7rc9:MessageBox doesn't represent a known control.
What am I doing wrong?
I want to convert windows user control into web user control..I have the usrDataView.cs..I need to convert this file into usrdataview.ascx.can anyonr help me?...how I can convert the file...Is any method is available..
View 1 Replieshave two user controls on one aspx page. UC1 has a grid which contains a link button column which user clicks. Based on the value of clicked cell, I need to show some data into UC2.How do I pass data from UC1 to UC2? How do I invoke a function of UC2 from UC1?
View 2 RepliesAll I would like to be able to do is include one user control within another! Is this possible? I have spent the last hour searching the internet and it seems that I can't find a single thing.
In classic ASP it would be something like:
<!--#include file="EditProject.ascx"-->
I tried this but no luck!
Parser Error Message:
There can be only one 'control' directive.
Source Error:
[Code]....
Line 1: <%@ Control Language="VB" AutoEventWireup="false" CodeFile="EditProject.ascx.vb"Line 2: Inherits="Controls_WebUserControl" %>Line 3: <form runat="server">
It's simple to create both user control from the two world : ASP.NET+Razor or MVC 3.0.But i do not known how to consume the user control FROM the razor"_layout.chtml" page.I want to put such thing within the layout page: <uc:MyTag Prop1="" Prop2="" />So i need to declare this directive at top of the layout file : <%@ Register TagPrefix="uc" TagName="MyTag" Src="Controls/Mytag.ascx" %>
View 1 RepliesI have the following problem;My console app is running on the server and all I want to do is control it over ASP.NET Web Service.
I added new ASP.NET Web Service project to my Solution where my main console app and added reference to it.The problem is every time WebMethod calls function from console app, i get the nullreferenceexception. Even if I try to use static classes or singletons; every object is null, although my console app is running absolutely correctly.
I am getting a NullReferenceException thrown when trying to add to theList object. Clueless at this point about how to solve.
[Code]....
When I submit invalid data to test my form validation I get a NullReferenceException on the folloing line of code in my view:
[Code]....
I can't seem to find anything that's null.assessment.AssessmentDescr is populated with the expected string.assessment.Score is populated with the value 0.Any ideas as to what might be causing the NullReferenceException? Seems to me that Html.TextBox has everything it nees to render the TextBox.
I followed the directions from MSDN on transferring data between asp.net pages.But when using the 'PreviousPage' property to access the previous pages controls, I get a null ref exception that PreviousPage is not set to an instance of an object.Here is my code:
public partial class Portal : System.Web.UI.Page
{
public string Username
[code]...
we have an MVC app that is after some time getting to some kind of bad state. I found only a couple of posts with a similar error message and they pointed to not changing up the routing table (after appstart). However this app doesn't mess with the routing table after appstart so that would appear not to be the cause of our problem. Recycling the app makes the error go away... for a time. Got 3 sites (all running of the same codebase) that this is effecting.
Just incase I'm doing something naughty in my application class heres a bit of source:
[Code]....
And the class that inherits from: [Code]....
Stack trace follows:[NullReferenceException: Object reference not set to an instance of an object.]
System.Web.Routing.RouteCollection.GetVirtualPath(RequestContext requestContext, RouteValueDictionary values) +97
I'm trying to call a dataadapter funtion to pass browser information to a database table upon logged in. I have also tried not assigning the function to an interget by setting the fucntion to not return a value. However in either case I get the System NullReferenceException.
[Code]....
I have some inline code in an aspx file that executes:
<dd><%= encode(Listing.Address.Line1) %> </dd>
Problem is, under certain circumstances the Listing object will be null and therefore references to properties such as Address will throw an exception. How do I handle that exception? I basically want to ignore it: catch it, and then proceed with regular execution/rendering of page.
I am having some issues accessing a literal in a usercontrol.
I get the following error: System.NullReferenceException: Object reference not set to an instance of an object. at page.sbPageLoad(String sTypeCD, Int32 iCategoryID, String SortExpression)
Does the following code below look right?
Here is my usercontrol named: topbanner.ascx:
Code:
[code]....
When I click on my btnMissionary_Click which is suppose to add a datatable row I am getting the following error:
System.NullReferenceException: Object reference not set to an instance of an object. If I add a entry right away it seems to work fine.
Here is my form
HTML Code:
<div id="container">
[code].....
Since I upgraded from MVC 2 to MVC 3 RC, using TryUpdateModel causes a NullReferenceException. This problem only occurs when running my action method as part of a unit test. Running it on the actual server works as expected. Here's a stack trace of the exception:
System.NullReferenceException: Object reference not set to an instance of an object. at System.Web.Mvc.JsonValueProviderFactory.GetValueProvider(ControllerContext controllerContext) at System.Web.Mvc.ValueProviderFactoryCollection.<>c_DisplayClassc.b_7(ValueProviderFactory
factory) at System.Linq.Enumerable.WhereSelectEnumerableIterator[Code]....
2.MoveNext()
at
System.Collections.Generic.List[Code]....
1
collection) at
System.Linq.Enumerable.ToList[TSource](IEnumerable`1
source) at
System.Web.Mvc.ValueProviderFactoryCollection.GetValueProvider(ControllerContext
controllerContext) at
System.Web.Mvc.Controller.TryUpdateModel[TModel](TModel
model, String prefix)
... my own code from here on....
In case it matters, my controller has the following signature:
[Code]....
My guess is that this has to do with the new way DI works in MVC3, but I can't figure out what I'm doing wrong. Perhaps there is something in terms of DI setup that is required in MVC 3, but wasn't required in MVC 2?
I am getting an exception like"NullReferenceException was unhandled by usercode-Object reference not set to an instance of an object." in (IEnumerable)Viewdata.Model.
<% foreach (EmployeeMaster m in (IEnumerable)ViewData.Model)