Hi all
i am having error is multi threaded application.
I have function in which i am opening form and starting thread.
But while doing this i am getting following error.
This exception is getting catched in main.
Does anyone know what is nativewindow.
Error:-
System.NullRefe renceException: Object reference not set to an instance
of an object.
at System.Windows. Forms.UnsafeNat iveMethods.Call WindowProc(IntP tr
wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows. Forms.NativeWin dow.DefWndProc( Message& m)
at System.Windows. Forms.Control.D efWndProc(Messa ge& m)
at System.Windows. Forms.Control.W ndProc(Message& m)
at System.Windows. Forms.Label.Wnd Proc(Message& m)
at System.Windows. Forms.ControlNa tiveWindow.OnMe ssage(Message& m)
at System.Windows. Forms.ControlNa tiveWindow.WndP roc(Message& m)
at System.Windows. Forms.NativeWin dow.Callback(In tPtr hWnd, Int32
msg, IntPtr wparam, IntPtr lparam)
Please help me.
Thanks in advance.
3  1132 
Are you trying to start a new thread in the WndProc Sub?
What are the messages you are trying to process in WndProc?
The object not set error is because you need to declare it as 'New', which
you haven't done.
Please let me/us know
hi
i have created every object using new operator still if i run
application more than 10 times my application is getting crash.
Is it a memory issue. Because even after allocating memory, after
executing some part of code, object becoming unreference.
Please help me.
Can you post code?
trialproduct2.. .@yahoo.com wrote: Hi all
i am having error is multi threaded application.
I have function in which i am opening form and starting thread.
But while doing this i am getting following error.
This exception is getting catched in main.
Does anyone know what is nativewindow.
Error:-
System.NullRefe renceException: Object reference not set to an
instance of an object.
at System.Windows. Forms.UnsafeNat iveMethods.Call WindowProc(IntP tr
wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows. Forms.NativeWin dow.DefWndProc( Message& m)
at System.Windows. Forms.Control.D efWndProc(Messa ge& m)
at System.Windows. Forms.Control.W ndProc(Message& m)
at System.Windows. Forms.Label.Wnd Proc(Message& m)
at System.Windows. Forms.ControlNa tiveWindow.OnMe ssage(Message& m)
at System.Windows. Forms.ControlNa tiveWindow.WndP roc(Message& m)
at System.Windows. Forms.NativeWin dow.Callback(In tPtr hWnd, Int32
msg, IntPtr wparam, IntPtr lparam)
Please help me.
Thanks in advance. This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
by: serge calderara |
last post by:
Dear all,
I have a function that I need to run in a thread due to the fact that it can
takes long time to execute according to the amount of data to collect.
This function is also populating a treeview control whne collected data gets
finished.
In order to achieve this I have used the following code :
System.Threading.ThreadPool.QueueUserWorkItem(New
System.Threading.WaitCallback(AddressOf GetListOfReelsFromRemoteDB))
|
by: Tony Proctor |
last post by:
Hi everyone
We're experiencing some serious anomalies with the scheduling of ASP
threads. I'd be interested to hear if anyone knows what algorithm is used
(e.g. simple round-robin, or something more sophisticated), and what
situations might perturb it. Even a hint as to what would be considered
normal scheduling might help.
The root of our problem is that we observed a normally well-behaved web
application suddenly limit itself to a...
|
by: Leonardo Hyppolito |
last post by:
Hello,
I am trying to write a multithread program that simulates producers and
consumers. My program can have many producers and many consumers (each in a
separate thread). It has a storage place (buffer) with "n" capacity. The
user provides these parameters on startup. The buffer works with a circular
queue.
It's a console application. My implementation is working with Semaphores
to synchornize everything. I think it's synchornized...
|
by: Ivan |
last post by:
Hi
I have following problem: I'm creating two threads who are performing some
tasks. When one thread finished I would like to restart her again (e.g. new
job). Following example demonstrates that. Problem is that when program is
started many threads are created (see output section), when only two should
be running at any time. Can you please help me to identify me where the
problem is?
Best regards
|
by: Bob Day |
last post by:
Using VS 2003, VB, MSDE...
There are two threads, A & B, that continously run and are started by Sub
Main. They instantiationsl of identical code. Thread A handles call
activity on telephone line 1 and Thread B handles call activity on telephone
line 2. They use a common SQL datasource, but all DataSets are unique to
each thread.
Is there a way for thread A to occasionally communication to thread B that
something has happened? ...
| | |
by: Charles Law |
last post by:
My first thought was to call
WorkerThread.Suspend
but the help cautions against this (for good reason) because the caller has
no control over where the thread actually stops, and it might have a lock
pending, for example.
I want to be able to stop a thread temporarily, and then optionally resume
it or stop it for good.
|
by: alundi |
last post by:
Greetings:
I'd like to post this as a new thread to an article in
microsoft.public.dotnet.languages.vb originally made by nevin and replied to
by Alan Pretre back in December ("ThreadState == not in the enumeration").
Like nevin, I have a VB.NET multi-threaded application, and quite
frequently, after my main application class will call Thread.Suspend() on the
thread the ThreadState of the Suspended Thread will be a value of 96. From...
|
by: Sergey Poberezovskiy |
last post by:
I have the following code in C# that I have trouble converting to VB(2.0):
private delegate void openDialog();
private void openWindowsDialog(openDialog open)
{
Thread thread = new Thread(new ThreadStart(open));
thread.SetApartmentState(ApartmentState.STA);
thread.Start();
}
|
by: Brad Walton |
last post by:
Hello. First post, but been doing a bit of reading here. I am working on a
project in Java, but decided to switch over to C# after seeing some of the
additional features I can get from C#. One of the big changes I want to make
is event-driven code (rather than the linear flow I had in Java). I have
spent a week or so searching Google, talking to a couple of programming
friends, and just chewing on it in my brain. I think I have an ok handle...
|
by: marktang |
last post by:
ONU (Optical Network Unit) is one of the key components for providing high-speed Internet services. Its primary function is to act as an endpoint device located at the user's premises. However, people are often confused as to whether an ONU can Work As a Router. In this blog post, we’ll explore What is ONU, What Is Router, ONU & Router’s main usage, and What is the difference between ONU and Router. Let’s take a closer look !
Part I. Meaning of...
|
by: Oralloy |
last post by:
Hello folks,
I am unable to find appropriate documentation on the type promotion of bit-fields when using the generalised comparison operator "<=>".
The problem is that using the GNU compilers, it seems that the internal comparison operator "<=>" tries to promote arguments from unsigned to signed.
This is as boiled down as I can make it.
Here is my compilation command:
g++-12 -std=c++20 -Wnarrowing bit_field.cpp
Here is the code in...
| | |
by: jinu1996 |
last post by:
In today's digital age, having a compelling online presence is paramount for businesses aiming to thrive in a competitive landscape. At the heart of this digital strategy lies an intricately woven tapestry of website design and digital marketing. It's not merely about having a website; it's about crafting an immersive digital experience that captivates audiences and drives business growth.
The Art of Business Website Design
Your website is...
|
by: Hystou |
last post by:
Overview:
Windows 11 and 10 have less user interface control over operating system update behaviour than previous versions of Windows. In Windows 11 and 10, there is no way to turn off the Windows Update option using the Control Panel or Settings app; it automatically checks for updates and installs any it finds, whether you like it or not. For most users, this new feature is actually very convenient. If you want to control the update process,...
|
by: tracyyun |
last post by:
Dear forum friends,
With the development of smart home technology, a variety of wireless communication protocols have appeared on the market, such as Zigbee, Z-Wave, Wi-Fi, Bluetooth, etc. Each protocol has its own unique characteristics and advantages, but as a user who is planning to build a smart home system, I am a bit confused by the choice of these technologies. I'm particularly interested in Zigbee because I've heard it does some...
|
by: agi2029 |
last post by:
Let's talk about the concept of autonomous AI software engineers and no-code agents. These AIs are designed to manage the entire lifecycle of a software development project—planning, coding, testing, and deployment—without human intervention. Imagine an AI that can take a project description, break it down, write the code, debug it, and then launch it, all on its own....
Now, this would greatly impact the work of software developers. The idea...
|
by: isladogs |
last post by:
The next Access Europe User Group meeting will be on Wednesday 1 May 2024 starting at 18:00 UK time (6PM UTC+1) and finishing by 19:30 (7.30PM).
In this session, we are pleased to welcome a new presenter, Adolph Dupré who will be discussing some powerful techniques for using class modules.
He will explain when you may want to use classes instead of User Defined Types (UDT). For example, to manage the data in unbound forms.
Adolph will...
|
by: 6302768590 |
last post by:
Hai team
i want code for transfer the data from one system to another through IP address by using C# our system has to for every 5mins then we have to update the data what the data is updated we have to send another system
| | |
by: muto222 |
last post by:
How can i add a mobile payment intergratation into php mysql website.
| |
