begininvoke

问题 In C# you use BeginInvoke like this: obj.BeginInvoke((Action)(() => { //do something })); I tried to translate it to VB.NET, and ended up with this code, that seems to work: obj.BeginInvoke( Sub() 'do something' End Sub ) The snippets look very different to me, especially because the (Action) (() => part is missing completely. Is this the correct way to use BeginInvoke in VB.NET? this is not a duplicate of How to use BeginInvoke C# because the question and every answer uses C# (if any

问题 I was told that Invoke() is similar to normal method calling... so why would people choose to use Invoke and not normal method calling? I tried to search online regarding the issue, what i get is the advantages of using BeginInvoke(), but what are the advantages of using Invoke()? 回答1: Use BeginInvoke when you want to call the delegate asynchronously (on a thread drawn from the thread pool) and Invoke if you want to call it synchronously. 回答2: It's worth noting first that we have to have

问题 I have the following: ThreadStart startThread = delegate { mySocket.StartListen(); }; mySocket is now looping on a Listen() when I: new Thread(startThread).Start(); Here is StartListen: public void StartListen() { Object locker = new Object(); // Lock resources lock (locker) { S = new System.Net.Sockets.Socket(System.Net.Sockets.AddressFamily.InterNetwork, System.Net.Sockets.SocketType.Stream, System.Net.Sockets.ProtocolType.Tcp); S.Blocking = false; try { S.Bind(serverEP); S.Listen(1000);

问题 Essentially, what are the differences between these beyond the obvious? When should I use which form? class What { public Go() { Thread thread = new Thread(new ThreadStart(Go2)); thread.Background = true; thread.Start(); } private Go2() { using UdpClient client = new UdpClient(blabla) { while (stuff) { client.Receive(guh); DoStuff(guh); } } } } versus class Whut { UdpClient client; public Go() { client = new UdpClient(blabla); client.BeginReceive(guh, new AsyncCallback(Go2), null); } private

问题 I want to write a class to simplify the asynchronous programing, like string s = mylib.BeginInvoek(test,"1"); here is my code: public T BeginInvokeExWithReturnValue<T>(Func<T> actionFunction) { ExecWithReturnType<T> execWtihReturnValue = new ExecWithReturnType<T>(actionFunction); IAsyncResult iar = execWtihReturnValue.BeginInvoke(new AsyncCallback(EndInvokeExWithReturnValue<T>), execWtihReturnValue); // how to code here to return value } private void EndInvokeExWithReturnValue<T>(IAsyncResult

问题 I want to write a class to simplify the asynchronous programing, like string s = mylib.BeginInvoek(test,"1"); here is my code: public T BeginInvokeExWithReturnValue<T>(Func<T> actionFunction) { ExecWithReturnType<T> execWtihReturnValue = new ExecWithReturnType<T>(actionFunction); IAsyncResult iar = execWtihReturnValue.BeginInvoke(new AsyncCallback(EndInvokeExWithReturnValue<T>), execWtihReturnValue); // how to code here to return value } private void EndInvokeExWithReturnValue<T>(IAsyncResult

问题 I'm trying to call System.Windows.Threading.Dispatcher.BeginInvoke . The signature of the method is this: BeginInvoke(Delegate method, params object[] args) I'm trying to pass it a Lambda instead of having to create a Delegate. _dispatcher.BeginInvoke((sender) => { DoSomething(); }, new object[] { this } ); It's giving me a compiler error saying that I can't convert the lambda to a System.Delegate. The signature of the delegate takes an object as a parameter and returns void. My lambda

问题 I've been working through my first project and have had a great deal a valuable help from the guys on SO but now I'm stuck again. The below sub is used to add TreeNodes to a TreeView, excluding certain filetypes/names, upon addition of new data: Sub DirSearch(ByVal strDir As String, ByVal strPattern As String, ByVal tvParent As TreeNodeCollection) Dim f As String Dim e As String Dim tvNode As TreeNode Dim ext() As String = strPattern.Split("|"c) Try For Each d In Directory.GetDirectories

问题 I have the following code to send a query to youtube and send the total result to a textbox. If I just alert the result, it's OK but I can't assign the result to a textbox. Please explain to me why? private void SearchVideo(string keyword) { string orderBy = ""; switch (cboSortBy.SelectedIndex) { case 1: orderBy = "published"; break; case 2: orderBy = "viewCount"; break; case 3: orderBy = "rating"; break; default: orderBy = "relevance"; break; } SearchDelegate sd = Search; sd.BeginInvoke

问题 I have a control which displays the state of an underlying asynchronous object. The object raises events, which arrive at the form, where they are essentially queued and eventually called using BeginInvoke. A problem arises when the control is disposed. Because things are happening asynchronously, meaning it is always possible that an event callback is queued during disposal, I sometimes get an InvalidOperationException (Invoke or BeginInvoke cannot be called on a control until the window