Search Results

Search found 7175 results on 287 pages for 'asynchronous processing'.

Page 5/287 | < Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >

• Serverside image processing

  - by spol

  I am designing a web application that does server side image processing in real time. Processing tasks include applying different effects like grayscale, blur, oil paint, pencil sketch etc on images in various formats. I want to build it using java/servlets which I am already familiar with. I found 3 options, 1) Use pure java imaging libraries like java.awt or http://www.jhlabs.com/ip/index.html 2) Use command line tools like Gimp/ImageMagick 3) Use c,c++ image libraries that have java bindings. I don't know which of the above options is good keeping the performance in mind. It looks like option 2) and 3) are good performance wise, but I want to be sure before I rule out 1). I have also heard gimp cannot be run using command line unless gtk or xwindows is already installed on the server. Will there be any such problems with 2) or 3) while running them server side? Also please suggest any good image processing libraries for this purpose.

  Read the article

• Parallel processing slower than sequential?

  - by zebediah49

  EDIT: For anyone who stumbles upon this in the future: Imagemagick uses a MP library. It's faster to use available cores if they're around, but if you have parallel jobs, it's unhelpful. Do one of the following: do your jobs serially (with Imagemagick in parallel mode) set MAGICK_THREAD_LIMIT=1 for your invocation of the imagemagick binary in question. By making Imagemagick use only one thread, it slows down by 20-30% in my test cases, but meant I could run one job per core without issues, for a significant net increase in performance. Original question: While converting some images using ImageMagick, I noticed a somewhat strange effect. Using xargs was significantly slower than a standard for loop. Since xargs limited to a single process should act like a for loop, I tested that, and found it to be about the same. Thus, we have this demonstration. Quad core (AMD Athalon X4, 2.6GHz) Working entirely on a tempfs (16g ram total; no swap) No other major loads Results: /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 1 convert -auto-level real 0m3.784s user 0m2.240s sys 0m0.230s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 2 convert -auto-level real 0m9.097s user 0m28.020s sys 0m0.910s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 10 convert -auto-level real 0m9.844s user 0m33.200s sys 0m1.270s Can anyone think of a reason why running two instances of this program takes more than twice as long in real time, and more than ten times as long in processor time to complete the same task? After that initial hit, more processes do not seem to have as significant of an effect. I thought it might have to do with disk seeking, so I did that test entirely in ram. Could it have something to do with how Convert works, and having more than one copy at once means it cannot use processor cache as efficiently or something? EDIT: When done with 1000x 769KB files, performance is as expected. Interesting. /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 1 convert -auto-level real 3m37.679s user 5m6.980s sys 0m6.340s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 1 convert -auto-level real 3m37.152s user 5m6.140s sys 0m6.530s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 2 convert -auto-level real 2m7.578s user 5m35.410s sys 0m6.050s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 4 convert -auto-level real 1m36.959s user 5m48.900s sys 0m6.350s /media/ramdisk/img$ time for f in *.bmp; do echo $f ${f%bmp}png; done | xargs -n 2 -P 10 convert -auto-level real 1m36.392s user 5m54.840s sys 0m5.650s

  Read the article

• Looking for a software / something to automate some simple audio processing

  - by Daniel Magliola

  I'm looking for a way to take a 1-hour podcast MP3 file and split it into several several 2-minute MP3s. Along the way, I'd like to also do a few things like Amplify the volume. The problem I'm solving is that I have a crappy MP3 player that won't let me seek forward or backward, nor will it remember where I left it when I turn it off, plus, I listen to these in a seriously high-noise situation. Thus, I need to be able to skip forward in large chunks (2-5 minutes) to the point where I left it. Is there any decent way to do this? Audacity doesn't seem to have command-line capabilities. I'm willing to write some code, for example, to call something over the command line and get how long the MP3 file is, to later know how many pieces i'll have, and then say "create an MP3 with 0:00 to 2:00", "create an MP3 with 2:00 to 4:00", etc. I'm also willing to pay for the right tools if necessary. I also don't care how slow this runs, as long as I can automate it :-) I'm doing this on Windows. Any pointers / ideas? Thanks!

  Read the article

• Reminder: True WCF Asynchronous Operation

  - by Sean Feldman

  A true asynchronous service operation is not the one that returns void, but the one that is marked as IsOneWay=true using BeginX/EndX asynchronous operations (thanks Krzysztof). To support this sort of fire-and-forget invocation, Windows Communication Foundation offers one-way operations. After the client issues the call, Windows Communication Foundation generates a request message, but no correlated reply message will ever return to the client. As a result, one-way operations can't return values, and any exception thrown on the service side will not make its way to the client. One-way calls do not equate to asynchronous calls. When one-way calls reach the service, they may not be dispatched all at once and may be queued up on the service side to be dispatched one at a time, all according to the service configured concurrency mode behavior and session mode. How many messages (whether one-way or request-reply) the service is willing to queue up is a product of the configured channel and the reliability mode. If the number of queued messages has exceeded the queue's capacity, then the client will block, even when issuing a one-way call. However, once the call is queued, the client is unblocked and can continue executing while the service processes the operation in the background. This usually gives the appearance of asynchronous calls.

  Read the article

• WPF: Asynchronous progress bar

  - by SumGuy

  I'm trying to create a progress bar that will work asynchronously to the main process. I'm created a new event and invoked it however everytime I then try to perform operations on the progress bar I recieve the following error: "The calling thread cannot access this object because a different thread owns it" The following code is an attempt to send an instance of the progress bar to the event as an object, it obviously failed but it gives you an idea of what the code looks like. private event EventHandler importing; void MdbDataImport_importing(object sender, EventArgs e) { ProgressBar pb = (ProgressBar)sender; while (true) { if (pb.Value >= 200) pb.Value = 0; pb.Value += 10; } } private void btnImport_Click(object sender, RoutedEventArgs e) { importing += new EventHandler(MdbDataImport_importing); IAsyncResult aResult = null; aResult = importing.BeginInvoke(pbDataImport, null, null, null); importing.EndInvoke(aResult); } Does anyone have ideas of how to do this. Thanks in advance SumGuy.

  Read the article

• How to unit test asynchronous APIs?

  - by Ben Clayton

  Hi all. I have installed Google Toolbox for Mac (http://code.google.com/p/google-toolbox-for-mac/) into Xcode and followed the instructions to set up unit testing found here (http://code.google.com/p/google-toolbox-for-mac/wiki/iPhoneUnitTesting). It all works great, and I can test my synchronous methods on all my objects absolutely fine. However, most of the complex APIs I actually want to test return results asynchronously via calling a method on a delegate - for example a call to a file download and update system will return immediately and then run a -fileDownloadDidComplete: method when the file finishes downloading. How would I test this as a unit test? It seems like I'd want to the testDownload function, or at least the test framework to 'wait' for fileDownloadDidComplete: method to run. Any ideas much appreciated!

  Read the article

• Asynchronous PHP request (not AJAX)

  - by Renjith R

  Hi I am developing an eshop application. I am using webservice to create Order in Oracle database and websvc will give a response (OrderNumber) and I will inform customer that his Order (OrderNumber) is generated My problem The creation of order is taking too much time in backend system and user is keeping refreshing the page, On each refresh user is coming back to Order create Page, so user is able to click on create Order button again In such cases multiple orders are creating for same orderlines.I can restrict user to create only one order per session in case I got order number in websvc response and I can give ordernumber to customer in next page But real problem come when I didn't get response(Ordernumber) and user is refreshing page. request is already went to Backend system and it will create order and my applicaion will not get response Is there any method in PHP where we can asyncronously check the status of order if first request is initiated by user and it doesn't matter the furthur page navigation Please help me out.. Thanks in advance

  Read the article

• How can I mock this asynchronous method?

  - by Charlie

  I have a class that roughly looks like this: public class ViewModel { public ViewModel(IWebService service) { this.WebService = service; } private IWebService WebService{get;set;} private IEnumerable<SomeData> MyData{get;set;} private void GetReferenceData() { this.WebService.BeginGetStaticReferenceData(GetReferenceDataOnComplete, null); } private void GetReferenceDataOnComplete(IAsyncResult result) { this.MyData = this.WebService.EndGetStaticReferenceData(result); } . . . } I want to mock my IWebService interface so that when BeginGetStaticReferenceData is called it is able to call the callback method. I'm using Moq and I can't work out how to do this. My unit test set up code looks something like: //Arrange var service = new Mock<IWebService>(); service.Setup(x => x.BeginGetStaticReferenceData(/*.......don't know.....*/)); service.Setup(x => x.EndGetStaticReferenceData(It.IsAny<IAsyncResult>())).Returns(new List<SomeData>{new SomeData{Name="blah"}}); var viewModel = new ViewModel(service.Object); . .

  Read the article

• Asynchronous Image loading in certain custom UITableViewCells

  - by Dan

  So, I'm sure that this issue has been brought up before, but I haven't quite seen a solution for my specific problem. What I'm doing is loading a group of custom UITableViewCell's that are drawn using Loren Brichter's solution, each cell has some content, an icon (representing the user) that is asynchronously loaded into it, and a few other things. Eventually, I'm hoping to add support for images. Not every cell has an image, so in the creation of the cell, it determines if an image is required to be loaded and drawn into the cell. My problem is that I don't know how I can do that while keeping the image loaded asynchronously - with not every cell having the need to load an image (like needed with the icon) I'm not sure how to keep it in order when an cell is thrown off screen and re-rendered when the user scrolls over it. Each cell draws it content from an NSArray containing a custom object called FeedItem. All I'm really looking for is some sort of solution or idea to help me because right now I am at a loss. Thanks guys, I will appreciate the help.

  Read the article

• Asynchronous I/O on Mac OS X

  - by stas

  Hi, Meaning the C10K problem, what is the best way to do asynch I/O on Mac OS X (assume to use on Mac and iPhone/iPad)? On Linux our choice is epoll, on Windows is I/O Completion Ports. Top priority is performance and scalability (thousands of connections). Thanks

  Read the article

• Handling asynchronous responses

  - by James P.

  I'm building an FTP client from scratch and I've noticed that the response codes aren't immediate (which is no surprise). What would be a good approach for getting the corresponding code to a command? Below is an example of the output of Filezilla server. The response code is the three digits near the end of each line. (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> Connected, sending welcome message... (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> 220-FileZilla Server version 0.9.12 beta (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> 220-written by Tim Kosse ([email protected]) (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> 220 Please visit http://sourceforge.net/projects/filezilla/ (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> user anonymous (000057) 23/05/2010 19:43:10 - (not logged in) (127.0.0.1)> 331 Password required for anonymous

  Read the article

• asynchronous .js file loading syntax

  - by taber

  Hi, I noticed that there seems to be a couple of slightly different syntaxes for loading js files asynchronously, and I was wondering if there's any difference between the two, or if they both pretty much function the same. I'm guessing they work the same, but just wanted to make sure one method isn't better than the other for some reason. :) Method One (function() { var d=document, h=d.getElementsByTagName('head')[0], s=d.createElement('script'); s.type='text/javascript'; s.src='/js/myfile.js'; h.appendChild(s); })(); /* note ending parenthesis and curly brace */ Method Two (Saw this in Facebook's code) (function() { var d=document, h=d.getElementsByTagName('head')[0], s=d.createElement('script'); s.type='text/javascript'; s.async=true; s.src='/js/myfile.js'; h.appendChild(s); }()); /* note ending parenthesis and curly brace */

  Read the article

• Asynchronous Silverlight 4 call to the World of Warcraft armoury streaming XML in C#

  - by user348446

  Hello - I have been stuck on this all weekend and failed miserably! Please help me to claw back my sanity!! Your challenge For my first Silverlight application I thought it would be fun to use the World of Warcraft armoury to list the characters in my guild. This involves making an asyncronous from Silverlight (duh!) to the WoW armoury which is XML based. SIMPLE EH? Take a look at this link and open the source. You'll see what I mean: http://eu.wowarmory.com/guild-info.xml?r=Eonar&n=Gifted and Talented Below is code for getting the XML (the call to ShowGuildies will cope with the returned XML - I have tested this locally and I know it works). I have not managed to get the expected returned XML at all. Notes: If the browser is capable of transforming the XML it will do so, otherwise HTML will be provided. I think it examines the UserAgent I am a seasoned asp.net web developer C# so go easy if you start talking about native to Windows Forms / WPF I can't seem to set the UserAgent setting in .net 4.0 - doesn't seem to be a property off the HttpWebRequest object for some reason - i think it used to be available. Silverlight 4.0 (created as 3.0 originally before I updated my installation of Silverlight to 4.0) Created using C# 4.0 Please explain as if you talking to a web developer and not a proper programming lol! Below is the code - it should return the XML from the wow armoury. private void button7_Click(object sender, RoutedEventArgs e) { // URL for armoury lookup string url = @"http://eu.wowarmory.com/guild-info.xml?r=Eonar&n=Gifted and Talented"; // Create the web request HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(url); // Set the user agent so we are returned XML and not HTML //httpWebRequest.Headers["User-Agent"] = "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.0)"; // Not sure about this dispatcher thing - it's late so i have started to guess. Dispatcher.BeginInvoke(delegate() { // Call asyncronously IAsyncResult asyncResult = httpWebRequest.BeginGetResponse(ReqCallback, httpWebRequest); // End the response and use the result using (HttpWebResponse httpWebResponse = (HttpWebResponse)httpWebRequest.EndGetResponse(asyncResult)) { // Load an XML document from a stream XDocument x = XDocument.Load(httpWebResponse.GetResponseStream()); // Basic function that will use LINQ to XML to get the list of characters. ShowGuildies(x); } }); } private void ReqCallback(IAsyncResult asynchronousResult) { // Not sure what to do here - maybe update the interface? } Really hope someone out there can help me! Thanks mucho! Dan. PS Yes, I have noticed the irony in the name of the guild :)

  Read the article

• Pattern for limiting number of simultaneous asynchronous calls

  - by hitch

  I need to retrieve multiple objects from an external system. The external system supports multiple simultaneous requests (i.e. threads), but it is possible to flood the external system - therefore I want to be able to retrieve multiple objects asynchronously, but I want to be able to throttle the number of simultaneous async requests. i.e. I need to retrieve 100 items, but don't want to be retrieving more than 25 of them at once. When each request of the 25 completes, I want to trigger another retrieval, and once they are all complete I want to return all of the results in the order they were requested (i.e. there is no point returning the results until the entire call is returned). Are there any recommended patterns for this sort of thing? Would something like this be appropriate (pseudocode, obviously)? private List<externalSystemObjects> returnedObjects = new List<externalSystemObjects>; public List<externalSystemObjects> GetObjects(List<string> ids) { int callCount = 0; int maxCallCount = 25; WaitHandle[] handles; foreach(id in itemIds to get) { if(callCount < maxCallCount) { WaitHandle handle = executeCall(id, callback); addWaitHandleToWaitArray(handle) } else { int returnedCallId = WaitHandle.WaitAny(handles); removeReturnedCallFromWaitHandles(handles); } } WaitHandle.WaitAll(handles); return returnedObjects; } public void callback(object result) { returnedObjects.Add(result); }

  Read the article

• How to TDD Asynchronous Events?

  - by Padu Merloti

  The fundamental question is how do I create a unit test that needs to call a method, wait for an event to happen on the tested class and then call another method (the one that we actually want to test)? Here's the scenario if you have time to read further: I'm developing an application that has to control a piece of hardware. In order to avoid dependency from hardware availability, when I create my object I specify that we are running in test mode. When that happens, the class that is being tested creates the appropriate driver hierarchy (in this case a thin mock layer of hardware drivers). Imagine that the class in question is an Elevator and I want to test the method that gives me the floor number that the elevator is. Here is how my fictitious test looks like right now: [TestMethod] public void TestGetCurrentFloor() { var elevator = new Elevator(Elevator.Environment.Offline); elevator.ElevatorArrivedOnFloor += TestElevatorArrived; elevator.GoToFloor(5); //Here's where I'm getting lost... I could block //until TestElevatorArrived gives me a signal, but //I'm not sure it's the best way int floor = elevator.GetCurrentFloor(); Assert.AreEqual(floor, 5); } Edit: Thanks for all the answers. This is how I ended up implementing it: [TestMethod] public void TestGetCurrentFloor() { var elevator = new Elevator(Elevator.Environment.Offline); elevator.ElevatorArrivedOnFloor += (s, e) => { Monitor.Pulse(this); }; lock (this) { elevator.GoToFloor(5); if (!Monitor.Wait(this, Timeout)) Assert.Fail("Elevator did not reach destination in time"); int floor = elevator.GetCurrentFloor(); Assert.AreEqual(floor, 5); } }

  Read the article

• Waiting on multiple asynchronous calls to complete before continuing

  - by Chad

  So, I have a page that loads and through jquery.get makes several requests to populate drop downs with their values. $(function() { LoadCategories($('#Category')); LoadPositions($('#Position')); LoadDepartments($('#Department')); LoadContact(); }; It then calls LoadContact(); Which does another call, and when it returns it populates all the fields on the form. The problem is that often, the dropdowns aren't all populated, and thus, it can't set them to the correct value. What I need to be able to do, is somehow have LoadContact only execute once the other methods are complete and callbacks done executing. But, I don't want to have to put a bunch of flags in the end of the drop down population callbacks, that I then check, and have to have a recursive setTimeout call checking, prior to calling LoadContact(); Is there something in jQuery that allows me to say, "Execute this, when all of these are done."?

  Read the article

• How to block the UI during asynchronous operations in WPF

  - by mcintyre321

  We have a WPF app (actually a VSTO WPF app). On certain controls there are multiple elements which, when clicked, load data from a web service and update the UI. Right now, we carry out these web requests synchronously, blocking the UI thread until the response comes back. This prevents the user clicking around the app while the data is loading, potentially putting it into an invalid state to handle the data when it is returned. Of course the app becomes unresponsive if the request takes a long time. Ideally, we'd like to have the cancel button active during this time, but nothing else. Is there a clever way of doing this, or will we have to switch the requests to execute asynchronously using backgroundworker and write something that disables all the controls apart from the cancel button while a request is in progress?

  Read the article

• Adding dynamic controls to Silverlight application after WCF Service Asynchronous Callback

  - by Birk

  I'm trying to add some dynamic controls to my Silverlight page after a WCF call. When I try to add a control to I get an error: Object reference not set to an instance of an object. Here is a simplified version of my code: using edm = SilverlightBusinessApplication.ServiceRefrence; public partial class ListWCF : Page { edm.ServiceClient EdmClient = new ServiceClient(); public ListWCF() { EdmClient.GetTestCompleted += EdmGetTestCompleted; EdmClient.GetTestAsync(); } private void EdmGetTestCompleted(object sender, edm.GetTestCompletedEventArgs e) { //This is where I want to add my controls Button b = new Button(); LayoutRoot.Children.Add(b); //Error: Object reference not set to an instance of an object } } Is it not possible to modify the page after it has been loaded? What am I missing? Thanks

  Read the article

• Javascript Detect All Images (Including Asynchronous)

  - by Zach

  Is there a way in javascript to detect all images in a document, including those that may be loaded asynchronously (and maybe after the DOM is ready)? I'm looking to create a function that can detect if Google Analytics has been loaded by searching through the DOM looking for "__utm.gif". document.images doesn't seem to hold this image as it's loaded asynchronously and not displayed.

  Read the article

• Where do I handle asynchronous exceptions?

  - by Jurily

  Consider the following code: class Foo { // boring parts omitted private TcpClient socket; public void Connect(){ socket.BeginConnect(Host, Port, new AsyncCallback(cbConnect), quux); } private void cbConnect(IAsyncResult result){ // blah } } If socket throws an exception after BeginConnect returns and before cbConnect gets called, where does it pop up? Is it even allowed to throw in the background?

  Read the article

• Asynchronous IO in Java?

  - by thr

  What options for async io (socket-based) are there in java other then java.nio? Also does java.nio use threads in the backround (as I think .NET's async-socket-library does, maybe it's been changed) or is it "true" async io using a proper select call?

  Read the article

• How does one implement a truly asynchronous java thread

  - by Ritesh M Nayak

  I have a function that needs to perfom two operations, one which finishes fast and one which takes a long time to run. I want to be able to delegate the long running operation to a thread and I dont care when the thread finishes, but the threads needs to complete. I implemented this as shown below , but, my secondoperation never gets done as the function exits after the start() call. How I can ensure that the function returns but the second operation thread finishes its execution as well and is not dependent on the parent thread ? public void someFunction(String data) { smallOperation() Blah a = new Blah(); Thread th = new Thread(a); th.Start(); } class SecondOperation implements Runnable { public void run(){ // doSomething long running } }

  Read the article

• Asynchronous Completion Routines I/O, Pointer to routine encapsulated in class

  - by simplebutperfect

  I was wondering if there was anyway to use functions like ReadFileEx that require a pointer to a function in a class WITHOUT marking the function as static? Thanks in advance. SBP.

  Read the article

• Typesafe fire-and-forget asynchronous delegate invocation in C#

  - by LBushkin

  I recently found myself needing a typesafe "fire-and-forget" mechanism for running code asynchronously. Ideally, what I would want to do is something like: var myAction = (Action)(() => Console.WriteLine("yada yada")); myAction.FireAndForget(); // async invocation Unfortunately, the obvious choice of calling BeginInvoke() without a corresponding EndInvoke() does not work - it results in a slow resource leak (since the asyn state is held by the runtime and never released ... it's expecting an eventual call to EndInvoke(). I also can't run the code on the .NET thread pool because it may take a very long time to complete (it's advised to only run relatively short-lived code on the thread pool) - this makes it impossible to use the ThreadPool.QueueUserWorkItem(). Initially, I only needed this behavior for methods whose signature matches Action, Action<...>, or Func<...>. So I put together a set of extension methods (see listing below) that let me do this without running into the resource leak. There are overloads for each version of Action/Func. Unfortunately, I now want to port this code to .NET 4 where the number of generic parameters on Action and Func have been increased substantially. Before I write a T4 script to generate these, I was also hoping to find a simpler more elegant way to do this. Any ideas are welcome. public static class AsyncExt { public static void FireAndForget( this Action action ) { action.BeginInvoke(OnActionCompleted, action); } public static void FireAndForget<T1>( this Action<T1> action, T1 arg1 ) { action.BeginInvoke(arg1, OnActionCompleted<T1>, action); } public static void FireAndForget<T1,T2>( this Action<T1,T2> action, T1 arg1, T2 arg2 ) { action.BeginInvoke(arg1, arg2, OnActionCompleted<T1, T2>, action); } public static void FireAndForget<TResult>(this Func<TResult> func, TResult arg1) { func.BeginInvoke(OnFuncCompleted<TResult>, func); } public static void FireAndForget<T1,TResult>(this Func<T1, TResult> action, T1 arg1) { action.BeginInvoke(arg1, OnFuncCompleted<T1,TResult>, action); } // more overloads of FireAndForget<..>() for Action<..> and Func<..> private static void OnActionCompleted( IAsyncResult result ) { var action = (Action)result.AsyncState; action.EndInvoke(result); } private static void OnActionCompleted<T1>( IAsyncResult result ) { var action = (Action<T1>)result.AsyncState; action.EndInvoke( result ); } private static void OnActionCompleted<T1,T2>(IAsyncResult result) { var action = (Action<T1,T2>)result.AsyncState; action.EndInvoke(result); } private static void OnFuncCompleted<TResult>( IAsyncResult result ) { var func = (Func<TResult>)result.AsyncState; func.EndInvoke( result ); } private static void OnFuncCompleted<T1,TResult>(IAsyncResult result) { var func = (Func<T1, TResult>)result.AsyncState; func.EndInvoke(result); } // more overloads of OnActionCompleted<> and OnFuncCompleted<> }

  Read the article

• Web service performing asynchronous call

  - by kornelijepetak

  I have a webservice method FetchNumber() that fetches a number from a database and then returns it to the caller. But just before it returns the number to the caller, it needs to send this number to another service so instantiates and runs the BackgroundWorker whose job is to send this number to another service. public class FetchingNumberService : System.Web.Services.WebService { [WebMethod] public int FetchNumber() { int value = Database.GetNumber(); AsyncUpdateNumber async = new AsyncUpdateNumber(value); return value; } } public class AsyncUpdateNumber { public AsyncUpdateNumber(int number) { sendingNumber = number; worker = new BackgroundWorker(); worker.DoWork += asynchronousCall; worker.RunWorkerAsync(); } private void asynchronousCall(object sender, DoWorkEventArgs e) { // Sending a number to a service (which is Synchronous) here } private int sendingNumber; private BackgroundWorker worker; } I don't want to block the web service (FetchNumber()) while sending this number to another service, because it can take a long time and the caller does not care about sending the number to another service. Caller expects this to return as soon as possible. FetchNumber() makes the background worker and runs it, then finishes (while worker is running in the background thread). I don't need any progress report or return value from the background worker. It's more of a fire-and-forget concept. My question is this. Since the web service object is instantiated per method call, what happens when the called method (FetchNumber() in this case) is finished, while the background worker it instatiated and ran is still running? What happens to the background thread? When does GC collect the service object? Does this prevent the background thread from executing correctly to the end? Are there any other side-effects on the background thread? Thanks for any input.

  Read the article

< Previous Page | 1 2 3 4 5 6 7 8 9 10 11 12  | Next Page >