vb net update progress bar backgroundworker thread

…we each have more potential than we might ever presume to guess. I'm really glad somebody on the forum has recognised the glider. Void timer_Tick(object sender, EventArgs e) Timer.Tick += new EventHandler(timer_Tick) TimeSpan interval = new TimeSpan(0, 0, 0, 10, 0) The TimeSpan / DateTime object might help to determine the timed elapsed. Lets say as an example the work needs to be done every 60 seconds, well the timer can tick every second and it can update the progress bar but then on it's 60th tick (or after a minutes has expired) it runs the work and clears the progress bar. When it ticks it's updates the progress bar as normal but then when it ticks say the tenth time then it runs some other code. Synchronising the two timers could become tricky so why not use one timer that ticks away sometimes updaing the progress bar and Unexpectedly receive the interrupt rather than your intended code.Was thinking some more on this and you know what I don't think you need two timers at all. Interrupting a thread arbitrarily is dangerous, however,īecause any framework or third-party methods in the calling stack could Preemption between the if statement and worker.Interrupt. Which is not thread-safe because of the possibility of If ((worker.ThreadState & ThreadState.WaitSleepJoin) > 0) This avoids the need for the following test: Thread that’s not blocked, the thread continues executing until it next blocks,Īt which point a ThreadInterruptedException is Unless the ThreadInterruptedException is unhandled. Interrupting a thread does not cause the thread to end, Public void CancelAsync ( object userState) // Cancels an operation

Public event DownloadData CompletedEventHandler DownloadData Completed Public void DownloadData Async (Uri address, object userToken) Public void DownloadData Async (Uri address) Public byte DownloadData (Uri address) // Synchronous version These members are from the WebClient class: The following (the highlighted sections indicate code that is part of the pattern):

Offers a family of members that internally manage multithreading, similar to (which we’ll cover next), and WebClient in System.Net. Just a few classes in the Framework follow this The EAP is just a pattern, so these features must be You dont need to do any calculations yourself. This tells the progress bar how much to increment by between its minimum and maximum values.

Forwarding of exceptions to the completion event First, add a progress bar and set its Step property to 1.

WPF or Windows Forms controls when the worker completes Needing to explicitly start or manage threads. Simple means by which classes can offer multithreading capability without consumers The event-based asynchronous pattern (EAP) provides a Part 3: Using Threads The Event-Based Asynchronous

Vb net update progress bar backgroundworker thread