Every time that I want to make a thread in the ThreadPool I make a stupid little function like Worker_O below.[code]...
Is there a way in VB .net to cast from Sub(i as integer) to Sub(o as object) without making Worker_O? Worker_O is ugly to me.
I m trying to move all my drive's files into h drive firstly i have added all drives in threadpool for scanning and when scanning of any drive finish (Without waiting for other drive's complete ) it will move file's to h drive but it is not working as i wanted that's why i need two threadpool - one threadpool for scanning files and second threadpool for moving file's into drive's
View 11 RepliesWhen using teh system.threading.timer or threading.threadpool. queueuserworkitem, you are able to pass an object.
But wouldn't the garbage collector destroy the object even before the callback can be executed?[code]...
ret = (user_in.alloc_hrprdy * 60) - (user_in.security_last_logout - user_in.security_last_login) I have this code, and whenever i try to run it I always gets an error. I guess this part(user_in.security_last_logout - user_in.security_last_login). Both fields with a timestamp data type. By the way I want to get the time from a timestamp data type..
View 2 RepliesIs it possible to do something like this:
Dim ThisThing as ThisThingToolStripMenuItem.Text
So i can later in the code just do ThisThing = "whatever" ?
I was wondering if there's a way I can make my objects return their own variable name as a string, something like this:
Public Class MyClass
Public ReadOnly Property VariableName() As String
Get
[Code]....
Is this possible? I'm fairly sure it should be possible through the System.Reflection namespace, but I can't figure it out.
excuse my coding and term limitations. I'm still learning and have only done what I'd consider basic things. I tried to search this solution for hours and but I'm coming up with nothing.
What I want to do is to reference different check boxes using one loop.
Like this..For xItemNo = 0 To 3
[Code]...
I get the error "Public member 'Checked' on type 'Boolean' not found." I get the fact I'm not able to simply make the text of the code into a variable I can easily insert into the code at will. At least not how I'm trying to do it.How can I dynamically change the check box name I'm referencing in the loop so I don't have to duplicate the code over and over for every check box name?
Basically, It is a program that allows you to automatically click things.
Here is the
Public Class Form1
Private Declare Function GetAsyncKeyState Lib "user32" (ByVal vkey As Long) As Integer
[Code].....
What I wanted to do was make an option to have variations in tick time. I want to put in a check box, and if it is checked then there will be 10 "variations" in click time, ranging from 1 second too soon, to 1 second late.
I am trying to make a customer class that will simply make a bunch of controls (hotspots) Visible value = False.
For instance: WinStartSpot.visible = False
Thing is I have roughly 60 "spots" that need to be turned on and off as the user clicks through the program (its a very simple OS simulator) I tried to make a class using boolean return but that failed miserably. how to code a class like that?
Ok well just started to learn Vb 2008 and im trying to make an image move using the arrow keys..im trying to make a little game just for practicing and im having trouble getting my sprite to move.
View 4 RepliesI was wondering if there is a way of making a picture have the properties of a checkbox. I want to have clickable stars that change color (from white to yellow) everytime the user clicks on them to represent the rating they put on certain foods.
View 5 RepliesHere's the code that is causing my problem, I have no idea why though. All necessary services have been imported.
'Creates Prompt File
Sub CreateFile()
Dim createstring As String = ""
[Code].....
String s = "test"; String is a class, so to use it we should create an object of it. But rather we just make a reference of it and give it a value. How is it possible and what concepts are used in it. The metadata of String class shows the following :
[Code]...
I have a DataGridView object to which I've bound a list of objects (of type Asset) returned from a database query.I'm programming in VB using Visual Studio 2005.I want to grab two copies of the bound object (calling them oldAsset and newAsset) from the selected row in the DataGridView, update newAsset based on input from other controls on the form, and pass both oldAsset and newAsset to a function that will update the appropriate record in the DB.I try to grab the two copies like this:
Dim currentRow As DataGridViewRow = Me.AssetDataGridView.CurrentRow
Dim newAsset As Asset
newAsset = currentRow.DataBoundItem
[code]....
Opening a watch window on oldAsset and newAsset indicates that the appropriate values are pulled at this point. But when I try to change a property of just newAsset, like
newAsset.CurrentLocationID = cboLocations.SelectedValue
I see that the corresponding value in oldAsset is also changed. This is not what I want, but it's obviously what I'm telling the computer to do.
how this is written in VB.NET? This was an example I found on [URL]
ThreadPool.QueueUserWorkItem(delegate
{
var channelFactory = new ChannelFactory<ISimpleService>("*");
var simpleService = channelFactory.CreateChannel();
var asyncResult = simpleService.BeginGetGreeting("Daniel", null, null);
[code]....
i have this code which i run with queued 10,000, even when a max of 50 is set but the threadpool counts goes to high.
Public Sub DoWork(ByVal objItem As Object)
Dim objUrl as String = DirectCast(objItem, string)
Try
If objUrl Is Nothing Then
[code]....
EDIT:i use a this code to check the number of runing threads each second
Sub Timer1Tick(sender As Object, e As EventArgs)
tsslthreads.Text=string.Format ("Threads: {0}", Process.GetCurrentProcess().Threads.Count)
End Sub
I have a bunch of operations that need to be executed simultaneously. For this I'm using the thread pool to execute the tasks. I'd like to know if it's possible to consume some sort of Async Callback (similar to BackgroundWorker.DoWorkComplete) when each thread is finished. The reasoning behind this is that I have a windows service running that uses IPC to update a GUI and I need to know the time at which each specific thread finishes I've used background workers to do a set of tasks and they work perfectly, however, they take longer than I would like. I've timed the execution on my BGW method for a designated number of said tasks and it took 27 seconds, and the same set of tasks takes 4 seconds using the threadpool method. I've also tried using managed threads, to the same effect as the background workers.
View 5 RepliesI'm currently writing an application that is used to automate a certain task. Currently, it uses the threadpool (using up to 25 threads per the enduser's option). Each thread calls a function which will usually take about two minutes to finish, but it uses a While loop in order to repeat the process. This is my code to start the threads:
Private Sub ProcessAllItems()
For i As Integer = 1 To Me.numThreads.Value Step 1
Threading.ThreadPool.QueueUserWorkItem(New Threading.WaitCallback(AddressOf ProcessItem), i)
Next i
End Sub
The function "ProcessItem()" is the function that contains the While loop. The control "Me.numThreads" is a NumericUpDown control whose max value is set to 25. My question is...is this a good method to follow? To my knowledge after .NET Framework SP1 there is a max of 250 threads/CPU. However I've read the the threadpool is normally used for processing short-lived tasks. Should I be using background workers instead? If so, how could I start up to 25 background workers during runtime depending on the value of "Me.numThreads"?
currently i am using a threadpool that contain a number of thread. This number of thread can be different everytime, sometimes 5, sometimes 10, sometimes 15 and so on (multiple of 5). So now i have it working good by using for loop to queue the thread into threadpool. Now the problems is i do not know how to make the progress bar depending on my threadpool. I want my progress bar to complete only when all the thread are done. After searching google, i found that maybe it can be solve by using AutoResetEvent(false), but after i apply to my program, it still did not work, my program hang at xEvent.WaitOne() method and didnt proceed further, anyone can explain to me how to solve the problem? Or got any other ways? For your information, only 5 threads can be running at the same time as the requirement state so (so i set the setmaxthread to 5 already).
View 1 Repliesanybody familiar with these error? "There were not enough free threads in the ThreadPool object to complete the operation".im calling a web service in my windows application client.
View 16 Replieswhipped up this code real quick which uses a ThreadPool on Form Load to iterate through my subnet and tell me if there's a device communicating at each IP address.
some questions: Why am I able to update BOTH my label at the top AND the listbox, but I'm only using an .Invoke on the Listbox?How can I know how many threads are currently being used while that is executing?
What does the SyncLock do?I'm aware some people don't like the use of Application.DoEvents(). Is it ok to be using it in this instance or is there a better practice?For those wanting to try it out, drag a Label and a Listbox to a new form. Label is called "currentIPTextbox", Listbox is default name.
[Code]...
I prepare data to be processed, and saved to file. Since this process is slow, I want to delegate it to a parallel thread, so the main routine can end his work faster. The data is processed and saved to file by the "Sub ProcesarDatos", a routine on his instance of "FileProcessor class".
I call the code this way:
Dim
fp As
New
FileProcessor(DatosDeArchivo, Archivo & ".txt", Me)
ThreadPool.QueueUserWorkItem
(NewSystem.Threading.WaitCallback _
AddressOffp.ProcesarDatos))
I am using VB.NET 2008.Every now and then, ThreadPool.QueueUserWorkItem can take up to 500 msI checked the available thread, and it's not 0.What can cause ThreadPool.QueueUserWorkItem to take long sometimes, and how can I make it faster ?
Do While Not TerminateRisk
While qRiskSync.Count > 0
sItem = qRiskSync.Dequeue
[code]....
can somebody give ThreadPool example for application thats needs to get information to datagridview from thousands of sources? My application needs to work fast and without freezing and lag, but I cant figure out this threadpool thing. And would be nice if you could add this thing to example that when I set domainupdown value to 25 as example, it sets threads to 25. So its making work 25x faster. I haven't find any good example for this, only some C# examples but they haven't work after i converted those to vb.net.
View 1 RepliesI have a app that gathers and store updated data from a list of websites. My app use threadpool and each thread visits a site within the list and gathers the data. I want to create a stop button to stop/ prevent threadpool from running once it is clicked. How do I go about doing this?
View 1 Repliescurrently i am using a threadpool that contain a number of thread. This number of thread can be different everytime, sometimes 5, sometimes 10, sometimes 15 and so on (multiple of 5). So now i have it working good by using for loop to queue the thread into threadpool. Now the problems is i do not know how to make the progress bar depending on my threadpool. I want my progress bar to complete only when all the thread are done. After searching google, i found that maybe it can be solve by using AutoResetEvent(false), but after i apply to my program, it still did not work, my program hang at xEvent.WaitOne() method and didnt proceed further, anyone can explain to me how to solve the problem? Or got any other ways? For your information, only 5 threads can be running at the same time as the requirement state so (so i set the setmaxthread to 5 already).
View 2 RepliesI want to open a VB.net form using a ThreadPool with a maximum of 10 threads. I need to do this because, the form should open based on a live event and i need atmost 10 forms on the desktop at a time. If i open the form on every live event without using a ThreadPool, the desktop will be floaded with many forms. I am using QueueUserWorkItem method of threadpool to queue a method which opens the form. In this queued method, there is form1.show() statement called. But after displaying the form, this method finishes execution and again we have 10 threads available in the system. I somehow want to either keep this method running so that 1 thread is occupied or i want to keep the thread alive till the form1 is closed by the user. I want the 11th form to appear on the desktop, only when any of the existing forms out of the 10 (already on desktop) is closed.
View 2 RepliesBeen trying to implementing ThreadPool over a large and variable amount of data like the following:
public sub ProcessWorkItem(byval state as object)
Dim originalState as CustomStateInfo = CType(state, CustomStateInfo)
'Do stuff
[Code]....
This of course will bomb out if we have more than 64 items/threads being placed on the ThreadPool.
So, how would one process say x amount of items until there are no more items left to process?
I want to allow my user to add certain small pictures into a form which has a bigger pictures. My idea is to simply allow the user to move small pictureboxes that is set on the top of the form to wherever she wants it to be. My problem is that she may want more than one instance of the same picturebox. I am wondering if I can create a picturebox (complete with the picture) during run time?
View 2 Replieshow can i modify my object at run time? I have a form containing two panels; textbox, picturebox, and a label are in the panel1 where as panel2 is likely to be the user screen.. User drag the textbox from panel1 to panel2 and it is added there.. Now, i want to provide the facility to the user to modify the size using mouse similarly as we use to modify using mouse while making our forms.. It is like re sizing the button or picturebox at run time.
View 1 Replies