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BeginInvoke() and EndInvoke() not available in delegates for asynchronous execution of methods Messages   Related Types This message was discovered on microsoft.public.dotnet.vjsharp. Responses highlighted in red are from those people who are likely to be able to contribute good, authoratitive information to this discussion. They include Microsoft employees, MVP's and others who IMHO contribute well to these kinds of discussions. Post a new message to this list... Sameeksha Hi, The following code does not work in J#. IAsyncResult ar1 = sampleDelegate.BeginInvoke(new AsyncCallback(AsyncResultSample.MyCallback), new Object[] { (Int32)param, (Int32)param }); It gives compilation error as BeginInvoke not available for delegates. Anybody knows a way to handle asynchronous execution of methods in J#? Reply to this message...        pratap [MSFT] (VIP) BeginInvoke and EndInvoke take additional parameters. Ensure you are passing the right parameters. Here are a couple of examples: (1) It is legal to omit the call to EndInvoke if the result of the call is not important. In the following e.g. the delegate is invoked asynchronously and we wait till the call completes. /** @delegate */ public delegate void Proc(); public class myclass { public static void display() { System.out.println("hello world"); } public static void main(String [] args) { Proc p = new Proc(myclass.display); // invoke asynchronously System.IAsyncResult ar = p.BeginInvoke(null, null); // sleep until the call completes ar.get_AsyncWaitHandle().WaitOne(); } } (2) Optinaly, you can process the result of an asynchronous invocation by passing an asynchronous "completion routine" to the BeginInvoke method when you issue the call. In the following e.g. the completion routine is passed as the second-last argument to BeginInvoke. The completion routine is responsible for calling EndInvoke to harvest the results of the method call. To allow EndIvoke to be called at completion time a reference to the delegate is also passed in as the last parameter to BeginInvoke. /** @delegate */ public delegate int Proc(int i, int j); public class myclass { public static int sum(int i, int j) { return i + j; } public static void main(String [] args) { Proc p = new Proc(myclass.sum); System.AsyncCallback cb = new System.AsyncCallback(myclass.onCompletion); // invoke asynchronously System.IAsyncResult ar = p.BeginInvoke(2, 2, cb, p); System.out.println("Invoked asynchronously"); } public static void onCompletion(System.IAsyncResult ar) { System.out.println("Get the delegate"); Proc p = (Proc) ar.get_AsyncState(); System.out.println("Get the result"); int sum = p.EndInvoke(ar); System.out.println("The sum: " + sum); } } Hope this helps. Thanks for your interest in Visual J# .NET. pratap Visual J# .NET Team -------------------- >Thread-Topic: BeginInvoke() and EndInvoke() not available in delegates for asynchronous execution of methods [Original message clipped] IAsyncResult ar1 = sampleDelegate.BeginInvoke(new AsyncCallback(AsyncResultSample.MyCallback), new Object[] { (Int32)param, (Int32)param }); It gives compilation error as BeginInvoke not available for delegates. Anybody knows a way to handle asynchronous execution of methods in J#? > Reply to this message...        Sameeksha Hi, Thanks for your help. It helped me write BeginInvoke() function call. But when I try to write EndInvoke() in the way you have specified, it causes a compilation error saying that no such method EndInvoke(IASyncResult). I'm using XP Operating System + Whidbey version 8.0.40301.9. Is it taking any other type or number of parameters ? Please guide me. Sameeksha Reply to this message...     System.AsyncCallback System.IAsyncResult System.Object Ad MBR BootFX Best-of-breed application framework for .NET projects, developed by Matthew Baxter-Reynolds and MBR IT

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