I've created a Delegate that I intend to call Async. Module Level Delegate Sub GetPartListDataFromServer(ByVal dvOriginal As DataView, ByVal ProgramID As Integer) Dim dlgGetPartList As GetPartListDataFromServer The following code I use in a method Dim dlgGetPartList As New GetPartListDataFromServer(AddressOf AsyncThreadMethod_G...
I am looking into someone else's code and do not have much experience with anything to do with multi-threading. I came across this line of code: BeginInvoke((MethodInvoker)delegate() { btnCalibrate.PerformClick(); }); I was wondering why do this when just this would have worked: btnCalibrate.PerformClick(); Thanks for your answers. ...
what is wrong with this code below? The conn_PageDeleted is coming from a background thread and i am trying to update a label every time i get a call back. I get an error stating Parameter count mismatch. Here is the code: private void cmdDeletePage_Click(object sender, EventArgs e) { worker = new BackgroundWorker(...
I thought that calling BeginInvoke more than once on the same delegate instance would cause problems, but I tried it out and it works. Why is that? Is the IAsyncResult object returned with each BeginInvoke called unique instead of each instance of the delegate? In other words, do I only need one instance of the delegate to spawn multip...
I've inherited code where BeginInvoke is called from the main thread (not a background thread, which is usually the pattern). I am trying to understand what it actually does in this scenario. Does the method being called in the BeginInvoke get in line of messages that come down to the window? The docs say asynchronously, so that is m...
Hi, I'm attempting to follow a pattern for performing WCF data service queries using the Silverlight 4 beta. The following is my code: public CodeTables() { CodeCountries = new ObservableCollection<dsRealHomes.CodeCountries>(); dsRealHomes.RealHomesEntities myClient = null; myClient = staticGlobals.Rea...
Hi all, I started working with delegates last week and i am trying to update my gridview async on the background. All goes well, no errors or such but i dont get a result after my EndInvoke. does anyone know what i am doing wrong? Here is a code snippet: public delegate string WebServiceDelegate(DataKey key); protected void b...
I have been fighting with multi threading for few days. I dont understand what are different ways of multithreading. I have read little bit about backgroundWorker, little bit about creating an object of thread. Yesterday I saw in delegate example to implement multithreading by calling BeginInvoke. I dont understand are these differe...
I'm working on a heavily data-bound Win.Forms application where I've found some strange behavior. The app has separate I/O threads receiving updates through asynchronous web-requests which it then sends to the main/GUI thread for processing and updating of application-wide data-stores (which in turn may be data-bound to various GUI-eleme...
Hi, The following method does not apply the wpf changes (background = red) until the 2nd method (DoWork) exits: private void change() { Background = Brushes.Red; Dispatcher.BeginInvoke((Action) DoWork); } DoWork() takes several seconds to run and I don't really want to put it into a thread, as this code will be used in several...
Consider the code: class Work { public void DoStuff(string s) { Console.WriteLine(s); // .. whatever } } class Master { private readonly Work work = new Work(); public void Execute() { string hello = "hello"; // (1) is this an ugly hack ? var thread1 = new Thread(new Para...
In my code I subscribe to an event that happens on a different thread. Every time this event happens, I receive an string that is posted to the observable collection: Dispatcher currentDispatcher = Dispatcher.CurrentDispatcher; var SerialLog = new ObservableCollection<string>(); private void hitStation_RawCommandSent(object...
Hi, In order to avoid freezing of GUI, I wanted to run method connecting to DB asynchronously. Therefore I have written this: DelegatLoginu dl = ConnectDB; IAsyncResult ar=dl.BeginInvoke(null, null); bool result = (bool)dl.EndInvoke(ar); But it is still freezing and I do not understand why - I though BeginInvok...
I need a way to perform some action synchronously which should complete in half a second, but might just hang around for minutes. If it times out I don't care about the result. Here's the I'm doing it right now using compiler-generated delegate.BeginInvoke: static void Main() { bool disposed = false; var wait = new ManualResetEv...
I have a method, which I wish to execute on the UI message pump and thus do the following: private void SomeMethod() { BeginInvoke(new MethodInvoker(MethodToInvoke)); } private void MethodToInvoke() { // This method contains code that I wish to execute on UI message pump. } Now, the above works just fine when I create a Debu...
Hi, I'm getting this error: Invoke or BeginInvoke cannot be called on a control until the window handle has been created. On these lines: m_SplashForm.Invoke( new SplashStatusChangedHandle(delegate(string str) { m_SplashInterface.SetStatusInfo(str); }), new object[] { value } ); I'...
Hi, In a sample use of the BeginInvoke thread pool method: ... Func<string, int> method = someWorkMethod; IAsyncResult cookie = method.BeginInvoke("test", ... One of the expected parameters (the last one), in BeginInvoke is: object @object What does the @ signify ? Thanks, Scott ...
Hi, I went through several examples posted online but I cant answer my question. I have my 'p' variable that is being increased by 1 in the for loop. I want the UI to display the progress of calculation (to show how 'p' is increasing from 0 to 1000000). I do the calculation on the separate thread and the I call dispatcher to update the...
What's wrong in my code? It's not updating the TextBox and the ProgressBar while deleting files. Imports System.Windows.Threading Imports System.IO Class MainWindow Private Sub bt_Click(ByVal sender As Object, ByVal e As RoutedEventArgs) Handles bt.Click Dim sb As New System.Text.StringBuilder Dim files = IO...
In Silverlight 4 I have a custom service class which has an asynchronous Completed event. Inside the Completed event I take the returned data and invoke a populate method via something like this: private void service_Completed(object sender, CompletedEventArgs args) { Dispatcher.BeginInvoke(() => populateInbox(args.Jobs)); } priva...