Commented Code Won't Work - Time The Thread Start, The Variable CurrentFarm Have Changed.
Mar 1, 2011
Vb.net For each currentFarm in ......
If urlQueue.Count > 0 Then
Debug.Assert(currentFarm.isBusy = False)
Debug.Assert(currentFarm.WebClient.IsBusy = False)
[CODE]...
The commented code won't work. That's because by the time the thread start, the variable currentFarm have changed. So I create a new function and cache the currentFarm in the function parameter. No there will be a cache of currentFarm address (object is always a pointer) on a stack and that address is the one being passed to the System.Threading.Thread constructor.
View 5 Replies
ADVERTISEMENT
Mar 18, 2010
I have written a multithreaded crawler and the process is simply creating threads and having them access a list of urls to crawl. They then access the urls and parse the html content. All this seems to work fine. Now when I need to write to tables in a database is when I experience issues. I have 2 declared arraylists that will contain the content each thread parse. The first arraylist is simply the rss feed links and the other arraylist contains the different posts. I then use a for each loop to iterate one while sequentially incrementing the other and writing to the database. My problem is that each time a new thread accesses one of the lists the content is changed and this affects the iteration. I tried using nested loops but it did not work before and this works fine using a single thread.
Here is my
SyncLock dlock
For Each rsslink As String In finallinks
postlink = finalposts.Item(i)
[CODE]...
Finallinks and finalposts are the two arraylists. I did not include the rest of the code which shows the threads working but this is the essential part where my error occurs which is basically here postlink = finalposts.Item(i) i = i + 1
ERROR: index was out of range. Must be non-negative and less than the size of the collection. Parameter name:index
I tried copying it to a new list but dosent work.
View 9 Replies
Mar 10, 2010
I'm working with an inherited code base which contains thousands of lines of commented out code. I know the previous coder meant to save all his hard work for posterity rather than simply deleting it but: I will never read it and it just gets in the way. One problem example is that when I perform text searches for certain code segments I gets dozens of "false" hits in the commented code. Is there a quick/easy way to detect large blocks of commented out code? A clever RegEx perhaps? I happen to be working in VB.NET at this time and comment character is a single apostrophe.
View 7 Replies
Oct 13, 2009
I am a Java developer. I have the task of converting a VB class to Java.Can some VB developer comment the following VB code so that I can write its Java equivalent?
Public Class RmaValidationCode
' Values for test type
Public Const SOFTWARE_TEST_TYPE = 0
[code].....
View 2 Replies
Sep 2, 2010
My understanding is that thread.join will suspend the execution of code on the calling thread until the spawned thread finishes or is aborted...
With that in mind, I tried this:
For i = 1 to 50
threads = New Thread(AddressOf test)
threads.IsBackground = True
threads.SetApartmentState(ApartmentState.STA)
[CODE]...
However, the rest of the code runs when the loop finishes, not waiting for all the spawned threads to finish. Since the rest of the code needs the threads to finish (otherwise the rest will error).
View 4 Replies
Jul 24, 2011
I have custom asynchronous WebRequest class that I am testing to find out how fast the request will be cancelled and found some odd results, that starting 6 WebRequests with TPL and cancelling them right away takes 25 sec, but when I used just regular background threads it took only 5 sec.
Update: Running them without cancelling takes with Task.Start 9 sec and Thread.Start 3 sec accordingly.
Imports System.Net
Imports System.Threading
[Code]....
View 1 Replies
Jun 11, 2009
i want to have some web browsers which navigate wile the thread is running and my problem is that I want to use a web browser object from .net in a thread. when i put a webbrowser object in my form, called webbrowser1, i cant reach it in the thread's operation(start thread). when i type webbroeser1 in the thread it doesn't undrestand what webbrowser1 is.
View 5 Replies
Jul 23, 2010
i have to develop windows service which will copy files to different servers.So i have to do this task using multi-theading.But i have to start only 3-4 threads.So whenever one threads get finished then i have to start new thread so that count of thread should remain 3 or 4
View 5 Replies
Mar 6, 2011
how can i allow a progressbar to be changed on a seperate thread? my code keeps saying that i cannot access it because it was created on a seperate thread:
[Code]...
If it is not worth it, it is not fun - you say programmers are boring but i say they are worth it.
View 1 Replies
Jun 12, 2012
I have this code that checks if a thread or page has changed. But it always says it has changed. Because it does. Im currenlty checking the whole html page but i dont know a better way. Hers my code.
Public Class Form1
Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click
[Code]....
View 4 Replies
Mar 21, 2011
The code has gone bad. It is in debug mode and jumping around everywhere.
Error = "The process or thread has changed since last step."
Here is the code. I just create the file "start.csv" to initialize the shell command. This is very unstable for some reason. When I run line by line in debug mode it starts jumping around irrationally. It gives me versions of the above error.
Option Strict On
Option Explicit On
Imports System.IO
Module Module1
Public WithEvents Tmr As New Timers.Timer
[Code] .....
View 10 Replies
Dec 14, 2011
In an other post of mine, a discussion was going on to change the extensions of mdb so user does not recognize it as Access DB (this is important for me) I tried this and changed extension to xrd, ran the application and it gave error. Off course it could not find my mdb. How to handle this? Do I need to make all the connections again?
View 5 Replies
Sep 2, 2010
I have this problem:I have a vb.net class (visual studio 2010) :
....
Private nowTime As String
....
[code]....
View 1 Replies
Jan 3, 2010
How can I make an event that is raised when a variable or property is changed (or can I just put the code I would put in an event in the Set section of a property?
View 5 Replies
Feb 24, 2012
im using the timer control, how do i set the start time and finish time? for eg, show a label text for 4 secs then hide. Googled for examples but still no joy.
View 4 Replies
Mar 27, 2012
I have a UserControl that has a ProgressBar on it. The purpose of the UserControl is to be able to show the progress % on the ProgressBar as text. To do this it uses the MyBase.Paint event. To make it work the ProgressBar is made invisible and the UserControl is 'painted' with an image of the ProgressBar and then the text is painted on top. The UserControl has a Value property that is passed through to the ProgressBar.Value property.
I use this UserControl in two places, on a Splash form (not a standard Splash Screen) and also on the main form of the application. It works on the Splash form but not on the main form - by work I mean that changes to the ProgressBar.Value property cause the ProgressBar to show its progress. The cause appears to be that in the Splash form case the MyBase.Paint event is called as a consequence of calling Me.Refresh in the Set procedure of the UserControl.Value property, in the main form case it isn't,
i.e. Me.Refresh isn't causing MyBase.Paint to run.
The main form has two BackgroundWorker components. The first gets called (RunWorkerAsync) from Form_Load after the Splash form has been shown. The BackgroundWorker.ProgressChanged event updates the Value property of the UserControl and it works exactly as intended. The second gets called as a result of a user starting an operation and again the BackgroundWorker.ProgressChanged event updates the Value property of the UserControl but MyBase.Paint doesn't run so the ProgressBar remains resolutely static.
Any ideas why it won't respond to Me.Refresh in one case but does in the other? Happy to make any of the code avaialble but didn't want to fllod the first post with reams of it. Here's what I think are the most relevant code sections. First the UserControl
[Code]...
View 12 Replies
Dec 13, 2011
I have a couple properties and functions that I use to determine which shift it is, and also use it to control the input during break periods.
Imports EfficiencyPlus.EfficiencyPlusBasic
Public Class ShiftChanger
Private ReadOnly Property shiftStarts As List(Of Date)
[code].....
View 1 Replies
Jan 29, 2011
I have a usercontrol in my application and inside of this usercontrol I have a declaration:
[Code]....
View 7 Replies
Apr 2, 2010
Is there a way to check if the date time picker has been changed? I have a date time picker set to allow a person to put in their date of birth and I have it set to no greater date than 12/1/1992, but I need to check that the user has actually selected a date before the form is submitted. Can it be checked?
View 6 Replies
Feb 17, 2012
I have a basic form which call functions on a numbers of different forms up to (30), Do these functions run in parrallel, or are they run sequentually.Each function as present calls for disk access, if the threads are running in series, this will present a considrable relay, this is not acceptable.
View 10 Replies
Nov 16, 2011
Check process handle count:In Task manager, View, Select columns, mark Handle Count to the view.(The process when loaded has about 333 handles)
Operation:The new thread is set equal to an existing thread, then the existing thread is started and aborted. How does one restore the old handle count? Why do the handles increase by a random number and do not revert?
How can Idisposable/CloseHandle/or GC.collect, Finalize() work in this situation? I'm trying to return the handles to their original count, 333, when I start a new thread it adds 4,5, or 6 handles per new thread(even if the thread is aborted and set to nothing).
[Code]...
View 6 Replies
Jun 7, 2010
Could anybody tell me which event is good to start the thread to load resultset?
Example :
Dim Table As DataTable
Sub LoadItem
Dim BL As New BLItem
BL.LoadResultSet()
[Code]...
View 2 Replies
Mar 16, 2011
I am new with threads in vb.net. I write the following code i use imports system.threading
declare thread as dim read as thread Then on a start btn click i write the following code
[Code]...
View 6 Replies
Nov 3, 2010
Is there an event that I can handle that is fired when the computers system time is changed?
My program timestamps things, and I want to make sure the time is correct. So when the program starts, I will run a query (SELECT GETDATE()) from my SQL server, and record the difference, in seconds, between the SQL server time, and the time returned from NOW(). Then when I timestamp things, I will just adjust the time. I cannot run a query every time. But, if someone changes the clock on the computer, that would throw the timestamp off. So I need a way to know when this has happened, so I can recalculate the difference.
View 3 Replies
Jul 10, 2011
I want to start the time in one user only because when i add a user in my listview and click the start button both of them start their time. how can only start one user only? and when i select the other user and start their time the first one that i start is continues deducting a time.
This is my code:
Public Class Form1
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
With Timer1
.Interval = 1000 '// set interval to 1,000, which is 1 second.
[CODE]...
View 8 Replies
Oct 14, 2011
I have a folder which consists of 13 files. I want if a file contains human readable code than count the number of commented lines, line of code, and otherwise ignore the file.
View 4 Replies
Mar 2, 2012
i am trying to create a module that will start a thread to go do something. once the "something" is done i want to notify the calling form that the event is complete. i left out the thread stuff since its not relevant to the question. the following code would work fine in VB6, but .net sees it as an error because FRM does not have a FRM.done, "DoSomething" would could called by multiple forms [Code]
View 2 Replies
May 14, 2011
I am creating a CHAT interface for my game (when networking, server/client style) and I ran into a little problem..The way it works... I have forms for the SERVER (frmServer) and CLIENTS (frmClient) each of them have a LISTBOX (lbChat) in which I input (lbChat.Items.Add(string)) text as the users type it - in essence a chatbox...
So, let's use the CLIENT as an example (as it is simpler and the concept the same in both client and server cases)The Client form (frmClient) creates a thread that is used to listen for chat messages (via TCP) - so what I did was pass the listbox itself (lbChat) to the thread thus (I thought) solving my problem of writing into the listbox when chat messages arrive (and are caught by the thread and not frmClient of course)Now while debugging the code I get the following exception when my thread attempts to write in the listbox (lbChat) of frmClient General Exception: System.InvalidOperationException: Cross-thread operation not valid: Control 'lbChat' accessed from a thread other than the thread it was created on.
So now the question is how do I work around this cross-thread exception? How do I pass information (chat text) from my listener threads (and there will be multiple of them in the field, one per client) to the centralized listbox (lbChat) on the form?I need some kind of method to transfer information while also reducing the chances of running into contention issues (do I need to use ReaderWriterLock?), thing is I have no clue how to accomplish this task (I thought simply passing in the listbox would allow me to write to it in each of the threads).
[Code]...
View 1 Replies
Aug 19, 2009
i have a timer and i want its calculation will be done on another thread, since the timer tick event start whenever its enable property is set to true i don't see how to force it to work in another thread.
View 6 Replies
Nov 3, 2009
Why this: System.Threading.Thread.CurrentThread.Priority = System.Threading.ThreadPriority.Highest doesn't work? I ran my app and checked it using the task manager process tab. It was checked as normal.
View 8 Replies
