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?
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Wpf - Repeating BackgroundWorker Task Using DistpatcherTimer?
Oct 28, 2011I'm trying to figure out the best way to approach this. I have a BackgroundWorker which is being used to make a socket connection on a timer.
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edit: thinking about it. It would be good if I could somehow build a watchdog into it, so if the BackgroundWorker thread is found to be running for more than 2 seconds, it's terminated as this would indicate the thread has been held up by the tcp connection.
Cancel Current BackgroundWorker Task Before Running Again?
Aug 1, 2010I'm using a BackgroundWorker to perform some analysis on a separate thread. The BackgroundWorker is called when a user clicks a CheckBox.
I need to provide for the user clicking the CheckBox, starting the BackgroundWorker task, and then changing their mind and clicking the CheckBox again.I simply want to cancel the currently running task and set the analysis off again. Currently I have the following method:
Public Sub UpdateParkStatusAsync()
Try
'Debug output.
Console.WriteLine("UC_Map_ViewModel.UpdateParkStatus called.")
[code]....
Backgroundworker - Multiple Background Workers - Only Last Task Completes?
Jan 26, 2011I have been pulling my hair out trying to get this to work. If I step through the code in debugger it all works great. My problem is if I just run it, only the last task responds. I'm guessing I am overwriting the background working or something. I am sure I am doing a few things wrong but my code is now messy as I tried many way while searching. I know of the threadpool and .Net 4.0 tasks but having a hard time getting to do what I need.
Basicly I am writing a program (trying more likely) that takes a list of computers and pings then, then checks their uptime and reports back.This works fine in the UI thread (Obviously that locks up my screen). I can have the background worker just do this, but then it does each computer 1 by one, and while the screen is responsive it still takes a long time.
So my answer was to have a for loop for each server launching a new background worker thread. My solution does not work.I have seen other threads that I could do it, but I need to use with events to call code to update to UI when each is done.
What is the most simple way to do this?
Here is my code. Most is just copy paste + modify till I get it working right.
So In the main class I have the testworker.
(I tried using Testworker() but it said I could not do that WithEvents)
When I click the button the list loads.
Private WithEvents TestWorker As System.ComponentModel.BackgroundWorker
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.Windows.RoutedEventArgs) Handles Button1.Click
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Difference Between MultiThread Or BackGroundWorker?
Mar 4, 2011the differences between multi threading and background worker and when I should be using either.
View 3 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.
Is It Guaranteed That Task A Started Before TaskB Will Be Completed Before Task B
Nov 24, 2010is it guaranted that a task A started before TaskB will be completed before task B assuming the task do the same level of operatons?or in other words is there a chance that a task B will finish before tast A in the assumption that the task calls the same procedure?
View 4 RepliesBackgroundworker 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)
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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).
.net - Use One BackgroundWorker To Do Different Activities?
Mar 11, 2011I am programming using VB.NET 2005. I am using a BackgroundWorker to load a large list or text file and process it.
Is it possible to use the same background worker to process something else, i.e. to process the text file that was loaded? somthing like
Dim bwkMain as New BackgroundWorker()
If its possible, how do I implement it in the same form as I have already implemented for the first one?
EDIT The question is: is it possible to use the same BackgroundWorker for another task, after it finishes one task?
.Net BackgroundWorker Hangs Up?
Mar 21, 2011I have limited experience in VB.net and have become stuck. I have tried to search for answers on other threads without success.I have an application that displays real time data.Queries are made to a MySQL database on another PC over the internet every 10 seconds to gather the most recent data.I have done the query within a BackgroundWorker so that the GUI is still responsive while the query is answered.What I've done works great for several hours or maybe for a couple of days but then the DoWork task appears to hang.
The code I'm using is to run the background worker is:
vb
If Not(backgroundWorker1.IsBusy) Then Me.backgroundWorker1.RunWorkerAsync() End If
The backgroundWorker runs just once and there's very little code in the DoWork routine:
vb
Private Sub backgroundWorker1_DoWork(ByVal sender As Object, ByVal e As System.ComponentModel.DoWorkEventArgs) Handles backgroundWorker1.DoWork rs = New
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Is there anyway I can set up a timeout on the maximum allowed time that the DoWork task can be active for? And if so how would I then go on to stop the backgroundWorker?I understand that CancelAsync isn't going to help as my DoWork task is not repeating as it runs once only, then stops and 10 secs later I run it again.
Add A BackgroundWorker To Application?
Jan 24, 2009I'm trying to add a backgroundWorker to my application, but I can't find it.I tried looking in the toolbox, but didn't find it. I looked in the Choose items dialog box and it is checked. Tried unchecking and checking it again, no difference.
I tried using Dim worker As System.ComponentModel.BackgroundWorker but get an error:
Type 'System.ComponentModel.BackgroundWorker' is not defined.Is there any way to add it to my program?
BackgroundWorker - Get Two Different RunWorkerCompleted?
Jun 26, 2009I used sample from jmcilhinney at Link to create background proces and it works like a charm. But. In my menu i have two (2) different toolstrip buttons which i need to run the same BackgroundWorker1_DoWork method, but different ackgroundWorker1_RunWorkerCompleted methods. Is that doable?
1. In BackgroundWorker1_DoWork method i use some time-consuming operation which at end sets two global variables.
2. In BackgroundWorker1_RunWorkerCompleted method I use some Select case statment based on that two global variables that are not the same for ToolstripButton1 and ToolstripButton2.
Vb.net
Private Sub FirstButtonToolStripMenuItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles FirstButtonToolStripMenuItem.Click
[code]....
BackgroundWorker - Not Working?
Apr 27, 2010Imports System.Net
Imports System.Text.RegularExpressions
Public Class Form1[code]....
This is my code, and it doesn't work. I can't see a results in TextBox.
Backgroundworker / Threading In WPF
Feb 21, 2011i'm trying to do a database search in my WPF program. And to give the program some speed, I want to use Backgroundworker or Threading. The problem is that i have to invoke the controls that the new thread is going it access. But i don't know to do this and i don't know i which event to put the code. Here is some code:
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BackgroundWorker And CookieJar?
Jun 19, 2009I am building an app that connects to a webservice that returns an XML file, and due to the lag I want to use a backgroundworker to connect and then return the data when its done, and also store the cookies in CookieJar so I can use one post to log in, and get the webservice to auth the session. However, I am completely stuck as I cant get BackgroundWorker to return anything other than a true or false when it completes. I am used to PHP now, until a few weeks ago it had been 5 years since I last used VB ( and it was vb6) so I am rusty.
View 1 RepliesBackgroundWorker And Non Responsive GUI?
Sep 19, 2010I cannot make it work. I'm a beginner, and not being sure what's really relevant I'll say I'm using VS2010 Express edition, on Windows7 Pro 64 bit.It's been bugging me for days, and I even thought it was because I was using Express edition, but it wasn't. I copied their Fibonacci example, and it worked as expected. Meaning: progress bar reported progress, GUI was responsive, so Cancel button could have done its part.
But I didn't want Fibonacci calculator, because recursive calls always make me think about stack overflow. I wanted something less fancy; I wanted simply to count to 100.000 and see the counter on the GUI changing all the time.So I followed the instructions on their Fibonacci example, but I made it only count "in its mind". It updated progress bar all the time, but text box shown only the last result after finished counting. Also GUI wasn't responsive, so I couldn't click cancel button.
When you start Fibonacci example, you could move the form around. But in my case, GUI was frozen, and form was moved only at the end of counting.
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Format DGV With A BackgroundWorker?
Apr 19, 2011I have an applictaion with a DGV which has many rows> I need to make different formattings depending on values from some columns. I was thinking to use event CellFormatting but it takes to much time. So, the other solution shoul be to use a backgroundWorker which will take care about formatting dgv.
Unfortunatelly I do not know exactly how to do that. I have tried in many ways but I have received the message:
Cross-thread operation not valid: Control 'StatusStrip1' accessed from a thread other than the thread it was created on.
Getting Backgroundworker To Work?
May 23, 2011I have not used Backgroundworker before and this one has me stumped. I have run examples (this is based on one from MSDN) and read what I could find, but I just can't seem to make this work. I am sure it is something simple that is wrong with my code, but don't know how to go about troubleshooting it. What happens is that it goes to the startthread() sub dim the object and sets the two variables and then bypasses the last line that starts the worker process. I'm stumped.
Here is the original code that works just fine, but hangs up my app (hence the need to run a background process)Above the is an Imports RARNET to support this:
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Use BackgroundWorker In A Module?
Jan 29, 2009how can i use BackgroundWorker in a module
View 9 Replies.net - Why Isn't BackgroundWorker.OnDoWork Getting Called
Apr 10, 2012I have a job object for long running operations that works like this:
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This worked fine a year ago, and I moved on to other things. I had to return to this code today, and when I run it now, the OnDoWork override is simply not called. A breakpoint in there isn't hit, debugging messages aren't written, the method is simply not called, and no errors are thrown anywhere. I can't think what would have changed that could cause this, since it seems like a low level framework thing. The rest of the app loads and runs fine, the main window shows (it's a WPF app), and button click events fire. It's just the background thread method that doesn't fire. What could be going on here?
Access Picturebox From A Backgroundworker?
Jan 23, 2012I have problem in my application to access a picturebox from a thread to make it visible or not.
When I try to change visibility from the thread, i get the above error, if i disabled crossthreading exception:
Me.CheckForIllegalCrossThreadCalls = False, the program run normally with no error but the image still not visible after i click the button (Start the thread and make picturebox1.visible = true)
change the visibilty of the picturebox from a thread (Backgroundworker).
Backgroundworker & Listview.items.add()?
Sep 8, 2010I'm using a vb.net backgroundworker thread for processing and I need to periodically add items to a listview (with multiple columns) during the thread processing.I can easily use the following code for delegating the task to add an item to a listview, but I can't figure out how to additional info to other columns on the same row.he thread, I'd execute the following to trigger the invoke to add to listview:AddListItem(ListView1, filepath)Here is the delegate code, if someone can show me how to add the t
Delegate Sub AddListItem_Delegate(ByVal [Label] As ListView, ByVal [text] As String)
Private Sub AddListItem(ByVal [ListView] As ListView, ByVal [text] As String, Optional ByVal [text2] As String = "")
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BackgroundWorker (Load Data From DB)
Aug 3, 2011I'm trying to load data from DB with a BackgroundWorker but I'm getting the follow error:
Quote"Cross-thread operation not valid: Control 'DataGridView1' accessed from a thread other than the thread it was created on" Well I didn't created any other thread or call it from other place, my code is just:
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Backgroundworker And UI Status Update?
Jun 29, 2011I am writing an application that calls data collectors (via ip or modem), collects data from them and reformats it. I had this much written when I was asked to make it multi-threaded so that I can collect from multiple sites at one time. I have that written using backgroundworkers and it appears to be working well. On my UI I have a text box that needs to update with status details like, dialing, collecting, reformatting, etc. I planned to simply write the status updates to the text box from an UpdateStatus routine. Found that had all sorts of nasty threading issues, so I added a delegate to call the status update routine. Problems seem to be fixed except that the updates to the UI are coming in chunks instead of one by one as they really occur. Can anybody tell me how to force the status update in the text box to update more asynchronously?
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