Difference Between MultiThread Or BackGroundWorker?
Mar 4, 2011the differences between multi threading and background worker and when I should be using either.
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Difference Between Task And Backgroundworker
Nov 15, 2010what is the difference between a task and a backgroundworker? when it is better to use one and when the other?
View 1 RepliesDifference Between Multi-threading Vs. Backgroundworker?
Apr 12, 2011I'm creating an app that needs to navigate to multiple websites, logs me in and then submits my documentation.I've read that multi-threading can handle this task but then I've read something about backgroundworker.
View 1 RepliesC# - Difference Between BackgroundWorker And System.Threading.Thread
Oct 24, 2009What is the difference between creating a thead using BackgroundWorker and creating a thread using System.Threading.Thread?
View 2 RepliesCancel Backgroundworker - Got The Error Message" This BackgroundWorker Is Currently Busy And Cannot Run Multiple Tasks Concurrently?
Dec 14, 2009in my button click event i ececure
If BackgroundWorker4.IsBusy Then
BackgroundWorker1.CancelAsync()
End If[code]....
after proceess completed if press the button again.i got the following error msg
This BackgroundWorker is currently busy and cannot run multiple tasks concurrently.
How To Multithread A Filestream
Feb 23, 2011I'm making a type of download manager which downloads parts of a file using HTTPREQUEST.addrange. The parts download without a problem and currently I use 5 instances of the same class to download the parts simultaneously each one downloading a different section of the file. Now my problem is that I don't want to save each part as a file then merge them later, I want to use a singular filestream and append everything asynchronously. In the code below I attempted to use the seek method but it feels like it changes the seek for all of the other parts as well.
[Code]...
How To Multithread With Timers
Nov 17, 2011how do I multithread using timers. For instance 3 picture boxes that change ever 3 seconds?
View 1 RepliesRaiseEvent Multithread?
Feb 24, 2011I have client/server app.I have a class for the tcpclient and a class for the tcplistenerIn my tcpclient class I have a system.timers.timerThe timer elapsed event fires a public event(in the tcpclient class) which the tcplistener class handles.During debugging I see the timer firing its elapsed event and calling raiseevent on the public method, yet the event is never fired in my tcplistener class.
View 1 RepliesUse Webbrowser In Multithread?
Sep 5, 2010I'm working on a project. It is a windows form app which has a webbrowser. The app navigates to a url automatically, checks the url's document, and jumps to another url (depends on the document). It works fine. But, now, the problem is the project needs check many urls, so, I'm trying to make it as a MDI form project. when the start button clicked, it create a control thread, in the thread, it launchs 10 MDI forms (within main form), each form does the work for different urls. once done, then launch the next 10 urls.
It works. However, I noticed that, although 10 MDI forms are open, the navigating part in their webbrowser seems run in sequencial. I thought these 10 MDI forms will load 10 urls at the same time, do the work at the same time, but I found that it seems they do load urls one by one, not at the same time.
so, I did some research, it seems webbrowser can only be run STA mode. does it mean I can not use multithread to load different urls at the same time?
basically, I want to have a multi tab webbrowser, and navigate to different urls in these tabs at the same time.
How Would I Multithread This Piece Of Code
Mar 3, 2009On this piece Of code I want to multithread, beginning where the for loop takes the data out of the array arydata. The threads would all do the same task.
View 1 RepliesVideo Capture And Multithread
Aug 10, 2009VB and programming on Windows as such. Mostly c++/gcc/linux. I am trying to build this VB app that shows a streaming video from a camera and that needs to be overlaid with some custom graphics and text. I used the code published here: [URL] to get the capture part to work. It essentially uses the avicap32.dll that most of you would probably know.
My plan:
1) Capture frames using SendMessage(windowHandle, WM_CAP_EDIT_COPY, 0, 0) and then copy from clipboard.
2) Do whatever graphics/text overlay on the obtained bitmap
3) send it to some picturebox on some form that is being shown
4) Do step 1 to 3 in a loop by a spawned worker thread.
Firstly is this a reasonable way to do what I want? or is there a much more efficient/easier way to about?
Now the specific problem: From my main thread directly if I do step 1 to 3 once UIComponent.DrawImage(VideoComponent.GetBitmap()) It shows me once captured image as it should and all is good.
Just to clarify: UIComponent is an object/instance that launches the Form and owns the picturebox I want to display on. VideoComponent is an object/instance that has started the videocapture and owns the picturebox to which the video is being captured. But if I wrap the same call above in a function and launch a thread that would start with that function as its starting point, I see a blank screen. Again, for testing purpose, I am only doing step 1 through 3 just once.
The thread part of the code is like this:
Private drawthread As Thread
public sub main()
drawthread = New Thread(AddressOf threadfunc)
[CODE]........
Handle Multithread Situation And Don't Lock?
Nov 25, 2009I have this situation: a Form with a System.Timer in it (with AutoReset = False). The form has its main thread and the timer its own thread too (nothing new here). When the user press a button I need to stop the timer, wait until the timer thread has stopped its execution and do something more.
On the other side, the timer updates an item at the form so BeginInvoke is used. The code looks like this:
Button Code: Private Sub ButtonStop_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ButtonStop.Click
[Code]...
The point is that I wait the main thread to let the timer thread to end its work.The problem is that this code deadlocks when the user clicks the button when the BeginInvoke is going to be called. How a simple thing like this one can be done? Looks like I cannot find a good solution to this problem
MultiThread In Client Server Application?
Aug 9, 2009SERVER
Im using this code:
Imports System.Threading
Imports System.Net.Sockets
[code]....
but when i tried to run the application, it hangs even if i wait several minutes.., is there something wrong with the code..
Open A File In Multithread Program?
Apr 30, 2011I have a multithread program and in a thread i read a stram from ftp server and write them to a file and close it and in another thread open saved file and read it for process.but sometime when i want to open saved file i receive a error that say : cannot open file , because another user open it .i create 2 filter that surly file saved and closed , but i don't success.
View 5 RepliesMultithread Approach - How To Create Instances Of Forms
Jan 21, 2010I have a program with 3 forms; each has a different role behind them. Form 1 loads when the program executes and the other 2 load by clicking on buttons from form 1. I would like to implement a multithreaded approach where even after clicking on form2 and form 3 I can still execute other form 1 options while form2 and form 3 contents execute. I read through some tutorials and still not to sure how to implement. I figured I need to create instances of the forms 2 and 3 but how to call the threads and control them? I did try a simple one and had some error concerning delegates.
View 4 RepliesMultithread Chat Server Side Crash
May 18, 2011The server connects, the clients connect, one client sends a message to the server, and the server broadcasts it to the other clients. But what I want to do now is to also have the server communicate with the clients. But when I click on the server form, it freezes, and I cant do nothing.
I think this is because of me not creating a thread for the communication(I saw this on another forum), but I dont know how to do that. I copied basically all the chat program code from a site, and I dont know much of sockets and what not.
Multithread Chat Server Side Crash?
May 18, 2011i'm doing a chat for a project, and it works like this. The server connects, the clients connect, one client sends a message to the server, and the server broadcasts it to the other clients. But what I want to do now is to also have the server communicate with the clients. But when I click on the server form, it freezes, and I cant do nothing. I think this is because of me not creating a thread for the communication(I saw this on another forum), but I dont know how to do that. I copied basically all the chat program code from a site, and I dont know much of sockets and what not.
View 2 RepliesMultithread Server/client And Text Box Input?
Nov 15, 2011How can I use a text box on a multithreaded client so that it will appear in the command line of the multithreaded server?We were given this code to work around/tear apart:
Imports System.Net.Sockets
Imports System.Text
Module Module1
[code]....
Multithreading - Multithread Populate Listview In .net Framework 2.0?
Jun 27, 2011i am new with multithreading in vbnet. i got this error.Cross-thread operation not valid: Control 'lvSample' accessed from a thread other than thethread it was created on.this is my code.
Private Sub xFormLoad(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
Dim t As Threading.Thread
[code].....
VS 2008 Multithread With Comm (bass Visualisation)?
Jan 21, 2010I have a thread executing the following:
vb
Do UpdateVis()
System.Threading.Thread.Sleep(Interval)
Loop
UpdateVis is as follows:
[Code]...
VS 2008 Successfully Multithread A Piece Of Software?
May 27, 2009I am trying to successfully multithread a piece of software I have been working on. I have an array of threads 'gen' already working, calling to a method taking a single integer as a parameter (done via typecasting).Now in this thread, when the function gets processed (for each thread a roughly 500 iteration while loop) the index seems to be getting mixed up. As far as I can tell, my threads are messing with eachother and warping values. Now this is happening in locally declared variables inside this function, not global variables.It may be useful to know that I am using a WebRequest via a call to another method. Don't know if that makes a difference or not.
View 7 RepliesVS 2008 - Multithread - Manipulate Something That Is In A Different Thread - Invoked Procedure ?
Jul 7, 2009I'm trying to manipulate something that is in a different thread, and I know I need to do something by the way of Invoked procedure, but I'm unclear on how. I looked up some examples here on the forums and tried to follow the basic template, but I continue to have the same problem. how to use invoke correctly.
Private Sub getMessage()
For Me.infiniteCounter = 1 To 2
'Try
[CODE]...........................
VS 2008 Multithread A Browser (visit Several Sites At A Time)?
Aug 16, 2009I currently have a browser go through the same list of sites one by one and gather updates. The problem though this takes awhile. Can a browser be multithreaded, (so it could visit several sites at a time) and if so would this take up a lot of server resources?
View 2 RepliesVS 2008 Return Listview Item Collection In Multithread?
Aug 31, 2009I am doing this within a thread:For Each item As ListViewItem In lvUsers.Items and I am getting: Cross-thread operation not valid: Control 'lvUsers' accessed from a thread other than the thread it was created on.I have been able to adjust a control in a way using something like:
Public Delegate Sub ListAddNameInvoker(ByVal text As String)
Public Sub ListAddName(ByVal text As String)
If lvUsers.InvokeRequired Then
[code]....
But how do I get data from a control and pass it to another thread?
Call A The Multithread Process In Order To Execute Querry In SQL Server DB?
Sep 3, 2009I have simple ASP.net web form. With a simple click on a button i need to call a the Multithread process in order to execute my querry in SQL Server DB. I know that my querry willl take up to 45 min to be executed. While the process is running i need to display some status information like: Starting time, Time elapsed, % of completed...So after running the process i got the following error message: "Timeout expired. The timeout period elapsed prior to completion of the operation or the server is not responding."So i have 2 problems to fix:
Avoid getting timeout while processing/calling the stored procedure. I tried to add cmd.CommandTimeout = 1000 but it didn't work out!
Display correctly Time elapsed and % Completed while processing.
Here's my code in the main form:
Imports System
Imports System.Data
Imports System.Configuration
[code]....
Backgroundworker Inside Another Backgroundworker?
Apr 2, 2012i'm in the need to start a backgroundworker inside another one.Now...The first one BGW starts a for cycle, and inside this one there is the second BGW that has to upload an image to a server.The trouble is that, the progress event and the complete event of the internal BGW are never called.
View 11 RepliesBackgroundworker In .net?
Jun 21, 2010good example on backgroundworker control in vb.net for doing some process in background for ex a reading a doc file in textbox by using backgroundworker in vb.net?
View 2 RepliesSet A Backgroundworker As STA?
Jan 29, 2011Is it possible to set a backgroundworker as STA
View 1 RepliesWhat Is A BackgroundWorker
Nov 9, 2009what is this BackgroundWorker and how to use it? Can it be used as a replacement to System.Threading.Thread??
View 2 Replies.net - Lockwindowupdate And Backgroundworker?
Sep 8, 2010I've got a bit of a problem, I'm using a backgroundworker to do a lot of processing and it adds items to a listview with: AddListItem(ListView1, listItem)
Here is the delegate code to send the command to the listview outside of the thread:
Delegate Sub AddListItem_Delegate(ByVal [ListView] As ListView, ByVal [text] As Object)
Private Sub AddListItem(ByVal [ListView] As ListView, ByVal [text] As ListViewItem)
[Code]...
The problem is, as you might imagine, flickering of the listview. Can anyone help me out with a solution to execute a LockWindowUpdate(Me.Handle) command in the backgroundworker? I've tried creating a new delegate but it's not working (errors, I don't understand vb.net enough).