Search Results

Search found 166 results on 7 pages for 'begininvoke'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 1/7 | 1 2 3 4 5 6 7  | Next Page >

  • Performance implications of BeginInvoke

    - by AngryHacker
    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 my assumption. How does the framework prioritize when to kick off the method called by BeginInvoke?

    Read the article

  • Silverlight 4 accessing WCF Data Services: BeginInvoke frustrations.

    - by Gatmando
    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.RealHomesContext(); object userState = null; myClient.BeginExecute<dsRealHomes.CodeCountries>(new Uri("CodeCountries"), (IAsyncResult asyncResult) => { Dispatcher.BeginInvoke( () => { var test = myClient.EndExecute<dsRealHomes.CodeCountries>asyncResult).ToList(); } ); }, userState); } This is derived from a number of examples I've come across for WCF data services with silverlight. Unfortunately no matter how I try to implement the code i end up with the following error on 'Dispatcher.BeginInvoke': 'An object reference is required for the non-static field, method, or property (System.Windows.Threading.Dispatcher.BeginInvoke(System.Action)' Thanks

    Read the article

  • Why is my BeginInvoke method not async?

    - by Petr
    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 BeginInvoke assures that method it references is run in another thread. Thank you!

    Read the article

  • BeginInvoke not invoking the target method in Release build

    - by Elan
    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 Debug build of the project. However, when I create a Release build, the "MethodToInvoke" method does not get invoked. Does anyone have any idea why this might be? Thanks, Elan

    Read the article

  • Understanding Thread/BeginInvoke? [beginner]

    - by Moberg
    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 ParameterizedThreadStart(o => this.work.DoStuff((string)o))); thread1.Start(hello); thread1.Join(); // (2) is this similar to the one above? new Action<string>(s => this.work.DoStuff(s)).BeginInvoke(hello, null, null); } } Is (1) an acceptable way of easy starting some work in a seperate thread? If not a better alternative would be much appreciated. Is (2) doing the same? I guess what I ask is if a new thread is started, or.. Hope you can help a beginner to a better understanding :) /Moberg

    Read the article

  • BeginInvoke on ObservableCollection not immediate.

    - by Padu Merloti
    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 sender, StringEventArgs e) { string command = e.Value.Replace("\r\n", ""); Action dispatchAction = () => SerialLog.Add(command); currentDispatcher.BeginInvoke(dispatchAction, DispatcherPriority.Render); } The code below is in my view model (could be in the code behind, it doesn't matter in this case). When I call "hitstation.PrepareHit", the event above gets called a couple times, then I wait and call "hitStation.HitBall", and the event above gets called a couple more times. private void HitBall() { try { try { Mouse.OverrideCursor = Cursors.Wait; //prepare hit hitStation.PrepareHit(hitSpeed); Thread.Wait(1000); PlayWarning(); //hit hitStation.HitBall(hitSpeed); } catch (TimeoutException ex) { MessageBox.Show("Timeout hitting ball: " + ex.Message); } } finally { Mouse.OverrideCursor = null; } } The problem I'm having is that the ListBox that is bound to my SerialLog gets updated only when the HitBall method finishes. I was expecting seeing a bunch of updates from the PrepareHit, a pause and then a bunch more updates from the HitBall. I've tried a couple of DispatcherPriority arguments, but they don't seem to have any effect.

    Read the article

  • Delegate, BeginInvoke. EndInvoke - How to clean up multiple Async threat calls to the same delegate?

    - by Dan
    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_GetPartListDataFromServer) dlgGetPartList.BeginInvoke(ucboPart.DataSource, ucboProgram.Value, AddressOf AsyncCallback_GetPartListDataFromServer, Nothing) The method runs and does what it needs to The Asyn callback is fired upon completion where I do an EndInvoke Sub AsyncCallback_GetPartListDataFromServer(ByVal ar As IAsyncResult) dlgGetPartList.EndInvoke(Nothing) End Sub It works as long as the method that starts the BeginInvoke on the delegate only ever runs while there is not a BeginInvoke/Thread operation already running. Problem is that the a new thread could be invoked while another thread on the delegate is still running and hasnt yet been EndInvoke'd. The program needs to be able to have the delegate run in more than one instance at a time if necessary and they all need to complete and have EndInvoke called. Once I start another BeginInvoke I lose the reference to the first BeginInvoke so I am unable to clean up the new thread with an EndInvoke. What is a clean solution and best practice to overcome this problem?

    Read the article

  • SQL Server 2008 Service Pack 1 and the Invoke or BeginInvoke cannot be called error message

    - by Jeff Widmer
    When trying to install SQL Server 2008 Service Pack 1 to a SQL Server 2008 instance that is running on a virtual machine, the installer will start:   But then after about 20 seconds I receive the following error message: TITLE: SQL Server Setup failure. ----------------------------- SQL Server Setup has encountered the following error: Invoke or BeginInvoke cannot be called on a control until the window handle has been created. ------------------------------ BUTTONS: OK ------------------------------ Searching for this issue I found that several people have the same problem and there is no clear solution.  Some had success with closing windows or Internet Explorer but that didn’t work for me; what did work is to make sure the SQL Server 2008 “Please wait while SQL Server 2008 Setup processes the current operation.” dialog is selected and has the focus when it first shows up.  Selected (with the current focus) it looks like this:   Without focus the dialog looks like this: Add a comment if you find out any information about how to consistently get around this issue or why it is happening in the first place.

    Read the article

  • C# parameter count mismatch when trying to add AsyncCallback into BeginInvoke()

    - by PunX
    I have main form (PrenosForm) and I am trying to run Form2 asynchronously. It works without callback delegate: this.BeginInvoke(cp, new object[] { datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt }, null); //works 1. Doesn't work with callback delegate (parameter count mismatch): this.BeginInvoke(cp, new object[] { datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt }, new AsyncCallback(callBackDelegate), null); //doesn't work parameter count mismatch 2. Works with callback delegate if I do it like this: cp.BeginInvoke(datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt, new AsyncCallback(callBackDelegate), null); //works 3. My question is why does one way work and the other doesn't? I'm new at this. Would anyone be so kind as to answer my question and point out my mistakes? private delegate void copyDelegat(List<ListViewItem> datoteke, string path, PrenosForm forma, DragDropEffects efekt); private delegate void callBackDelegat(IAsyncResult a); public void doCopy(List<ListViewItem> datoteke, string path, PrenosForm forma, DragDropEffects efekt) { new Form2(datoteke, path, forma, efekt); } public void callBackFunc(IAsyncResult a) { AsyncResult res = a.AsyncState as AsyncResult; copyDelegat delegat = res.AsyncDelegate as copyDelegat; delegat.EndInvoke(a); } public void kopiraj(List<ListViewItem> datoteke, DragDropEffects efekt) { copyDelegat cp = new copyDelegat(doCopy); callBackDelegat callBackDelegate = new callBackDelegat(callBackFunc); this.BeginInvoke(cp, new object[] { datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt }, new AsyncCallback(callBackDelegate), null); //doesn't work parameter count missmatch 2. this.BeginInvoke(cp, new object[] { datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt }, null); //works 1. cp.BeginInvoke(datoteke, this.treeView1.SelectedNode.FullPath.ToString(), this, efekt, new AsyncCallback(callBackDelegate), null); //works 3. }

    Read the article

  • WinForms Control.BeginInvoke asynchronous callback

    - by Darran
    I have a number of Janus grid controls that need to be populated on an application startup. I'd like to load these grids on different threads to speed startup time and the time it takes to refresh these grids. Each grid is on a seperate tab. Ideally I'd like to use Control.BeginInvoke on each grid and on the grid load completing the tabs will become enabled. I know with Delegates you can do a Asynchronous callback when using BeginInvoke, so I could enable the tabs in the asynchronous callback, however when using Control.BeginInvoke this is not possible. Is there a way to do asynchronous callbacks using Control.BeginInvoke or possibly a better solution? So far I have: public delegate void BindDelegate(IMyGrid grid); private IAsyncResult InvokeBind(IMyGrid grid) { return ((Control)grid).BeginInvoke( new BindDelegate(DoBind), new object[] { grid } ); } private void DoBind(IMyGrid grid) { grid.Bind(); // Expensive operation } private void RefreshComplete() { IAsyncResult grid1Asynch = InvokeBind(grid1); IAsyncResult grid2Asynch = InvokeBind(grid2); IAsyncResult grid3Asynch = InvokeBind(grid2); IAsyncResult grid4Asynch = InvokeBind(grid3); IAsyncResult grid5Asynch = InvokeBind(grid4); IAsyncResult grid6Asynch = InvokeBind(grid5); } Now I could spin off a separate thread and keep checking to see if the IAsynchResults have completed and depending on which one completes I could re-enable the Tab control that the grid is contained in. Is there a better way of doing this?

    Read the article

  • Dispatcher.BeginInvoke problems

    - by cmaduro
    I'm getting "An object reference is required for the non-static field, method, or property 'System.Windows.Threading.Dispatcher.BeginInvoke(System.Action)'" for this code. private void ResponseCompleted(IAsyncResult result) { HttpWebRequest request = result.AsyncState as HttpWebRequest; HttpWebResponse response = request.EndGetResponse(result) as HttpWebResponse; using (StreamReader sr = new StreamReader(response.GetResponseStream())) { Dispatcher.BeginInvoke( () => { try { XDocument resultsXml = XDocument.Load(sr); QueryCompleted(new QueryCompletedEventArgs(resultsXml)); } catch (XmlException e) { XDocument errorXml = new XDocument(new XElement("error", e.Message)); QueryCompleted(new QueryCompletedEventArgs(errorXml)); } }); } } }

    Read the article

  • Unresponsive UI when using BeginInvoke

    - by Kazoom
    Bckground I have a networked application written in C#. my server program has a UI and several communication threads, that read from tcp sockets and display messages on controller UI. Communication with each client is done through a seprate thread. When i recieve some stream of messages from one client , the thread for that client writes on UI, which is a richtextbox on a Form. I call SetTextHelper(string text) method of the form. which looks like this private delegate void MyTextUpdateHandler(string text); public void SetTextHelper(string text) { BeginInvoke(new MyTextUpdateHandler(SetText), new object[] { text }); } public setText(string text) { richtext.Text= text; } Question - If i use BeginInvoke my UI is entirely unresponsive when i m writing large stream of data to UI - Invoke solves that problem, but i read that for multi threaded environment where many thereads are sharing same resource Invoke can lead to deadlocks I share the common ichtextbox between around 16 threads - What would be a good desing for my situation?

    Read the article

  • Control.Invoke() vs. Control.BeginInvoke()

    - by user590088
    First of all, I would like to apologize for my bad grammar since English is not my native tongue. This is my understanding: Control.Invoke(delegated_method) // Executes on the thread wich the control was created on witch holds its handle ,typically this would be the main thread of a winform application . Control.BeginInvoke(delegated_method // Executes asynchronously on a threadPool Thread . According to MSDN, it says Executes a delegate asynchronously on the thread that the control's underlying handle was created on. My QUESTION : Am I to understand that beginInvoke treats the main thread in this matter as it would the thread pool, and execute the delegated method on the main thread when it "gets a chance" ? Another question which is raised, is it possible to create a control not on the main thread ? if so could someone give me an example?

    Read the article

  • WPF Dispatcher.BeginInvoke crash on Windows XP

    - by amr-ne
    Hi, I have a WPF application and a worker thread. The worker thread invokes a callback on the UI thread, which opens a new dialog. Works fine on Win7, but on XP it will crash. In worker thread: someWpfDialogInstance.Dispatcher.BeginInvoke(openSomeDialogCallback, null); Does someone knows a solution or a workaround for this problem?

    Read the article

  • Invoke or BeginInvoke cannot be called on a control until the window handle has been created

    - by blade3
    I am trying to install SQL Server 2008 Developer Edition x64 on a Windows Server 2008 VM. I run the installer for a standalone installation and this works fine for the setup support rules bit. That passes ok but then I get this error: TITLE: SQL Server Setup failure. SQL Server Setup has encountered the following error: Invoke or BeginInvoke cannot be called on a control until the window handle has been created.. BUTTONS: OK How can I resolve this? I am getting 2008 R2 CTP but this is just a CTP. My download is from DreamSpark. Thanks

    Read the article

  • Passing data to Winforms UI using BeginInvoke

    - by Bi
    I am a C# newbie and have a class that needs to pass row information to a grid in the windows form. What is the best way to do it? I have put in some example code for better understanding. public class GUIController { private My_Main myWindow; public GUIController( My_Main window ) { myWindow = window; } public void UpdateProducts( List<myProduct> newList ) { object[] row = new object[3]; foreach (myProduct product in newList) { row[0] = product.Name; row[1] = product.Status; row[2] = product.Day; //HOW DO I USE BeginInvoke HERE? } } } And the form class below: public class My_Main : Form { //HOW DO I GO ABOUT USING THIS DELEGATE? public delegate void ProductDelegate( string[] row ); public static My_Main theWindow = null; static void Main( ) { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); theWindow = new My_Main(); Application.Run(theWindow); } private void My_Main_Load( object sender, EventArgs e ) { /// Create GUIController and pass the window object gui = new GUIController( this ); } public void PopulateGrid( string[] row ) { ProductsGrid.Rows.Add(row); ProductsGrid.Update(); } }

    Read the article

  • C#: Passing data to forms UI using BeginInvoke

    - by Bi
    Hi I am a C# newbie and have a class that needs to pass row information to a grid in the windows form. What is the best way to do it? I have put in some example code for better understanding. Thanks. public class GUIController { private My_Main myWindow; public GUIController( My_Main window ) { myWindow = window; } public void UpdateProducts( List<myProduct> newList ) { object[] row = new object[3]; foreach (myProduct product in newList) { row[0] = product.Name; row[1] = product.Status; row[2] = product.Day; //HOW DO I USE BeginInvoke HERE? } } } And the form class below: public class My_Main : Form { //HOW DO I GO ABOUT USING THIS DELEGATE? public delegate void ProductDelegate( string[] row ); public static My_Main theWindow = null; static void Main( ) { Application.EnableVisualStyles(); Application.SetCompatibleTextRenderingDefault(false); theWindow = new My_Main(); Application.Run(theWindow); } private void My_Main_Load( object sender, EventArgs e ) { /// Create GUIController and pass the window object gui = new GUIController( this ); } public void PopulateGrid( string[] row ) { ProductsGrid.Rows.Add(row); ProductsGrid.Update(); } } Thanks!

    Read the article

  • WPF calls not working during long method processing

    - by Colin Rouse
    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 places and will probably interact will the Dispatcher thread at various intervals. I've tried calling the Invalidate...() methods, but to no avail. The BeginInvoke() was added to see if the delay would allow the background change to be applied before the logic was called. Typically, the logic would be part of this method. Btw, most of the logic is performed on a different thread and shouldn't block the Dispatcher thread?! Can someone please help? Thanks

    Read the article

  • Problems related to showing MessageBox from non-GUI threads

    - by Hans Løken
    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-elements, etc.). The server at the other end of the web-requests requires periodic requests or the session times out. I've gone through several attempted solutions of dealing with thread-issues etc. and I've observed the following behavior: If I use Control.Invoke for sending updates from I/O-thread(s) to main-thread and this update causes a MessageBox to be shown the main form's message pump stops until the user clicks the ok-button. This also blocks the I/O-thread from continuing eventually leading to timeouts on the server. If I use Control.BeginInvoke for sending updates from I/O-thread(s) to main-thread the main form's message pump does not stop, but if the processing of an update leads to a messagebox being shown, the processing of the rest of that update is halted until the user clicks ok. Since the I/O-threads keep running and the message pump keeps processing messages several BeginInvoke's for updates may be called before the one with the message box is finished. This leads to out-of-sequence updates which is unacceptable. I/O-threads add updates to a blocking queue (very similar to http://stackoverflow.com/questions/530211/creating-a-blocking-queuet-in-net/530228#530228). GUI-thread uses a Forms.Timer that periodically applies all updates in the blocking queue. This solution solves both the problem of blocking I/O threads and sequentiality of updates i.e. next update will be never be started until previous is finished. However, there is a small performance cost as well as introducing a latency in showing updates that is unacceptable in the long run. I would like update-processing in the main-thread to be event-driven rather than polling. So to my question. How should I do this to: avoid blocking the I/O-threads guarantee that updates are finished in-sequence keep the main message pump running while showing a message box as a result of an update.

    Read the article

  • Why doesnt the AsyncCallback update my gridview?

    - by Naruji
    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 btnCheckAll_Click(object sender, EventArgs e) { foreach (DataKey key in gvTest.DataKeys) { WebServiceDelegate wsDelegate = new WebServiceDelegate(GetWebserviceStatus); wsDelegate.BeginInvoke(key, new AsyncCallback(UpdateWebserviceStatus), wsDelegate); } } public string GetWebserviceStatus(DataKey key) { return String.Format("Updated {0}", key.Value); } public void UpdateWebserviceStatus(IAsyncResult result) { WebServiceDelegate wsDelegate = (WebServiceDelegate)result.AsyncState; Label lblUpdate = (Label)gvTest.Rows[Convert.ToInt32(key.Value)].FindControl("lblUpdate"); lblUpdate.Text = wsDelegate.EndInvoke(result); }

    Read the article

  • Can you have too many Delegate.BeginInvoke calls at once?

    - by stewsha
    I am cleaning up some old code converting it to work asynchronously. psDelegate.GetStops decStops = psLoadRetrieve.GetLoadStopsByLoadID; var arStops = decStops.BeginInvoke(loadID, null, null); WaitHandle.WaitAll(new WaitHandle[] { arStops.AsyncWaitHandle }); var stops = decStops.EndInvoke(arStops); Above is a single example of what I am doing for asynchronous work. My plan is to have close to 20 different delegates running. All will call BeginInvoke and wait until they are all complete before calling EndInvoke. My question is will having so many delegates running cause problems? I understand that BeginInvoke uses the ThreadPool to do work and that has a limit of 25 threads. 20 is under that limit but it is very likely that other parts of the system could be using any number of threads from the ThreadPool as well. Thanks!

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

1 2 3 4 5 6 7  | Next Page >