delegates

问题 I started to use the method group syntax a couple of years ago based on some suggestion from ReSharper and recently I gave a try to ClrHeapAllocationAnalyzer and it flagged every location where I was using a method group in a lambda with the issue HAA0603 - This will allocate a delegate instance . As I was curious to see if this suggestion was actually useful, I wrote a simple console app for the 2 cases. Code1: class Program { static void Main(string[] args) { var temp = args.AsEnumerable();

问题 I started to use the method group syntax a couple of years ago based on some suggestion from ReSharper and recently I gave a try to ClrHeapAllocationAnalyzer and it flagged every location where I was using a method group in a lambda with the issue HAA0603 - This will allocate a delegate instance . As I was curious to see if this suggestion was actually useful, I wrote a simple console app for the 2 cases. Code1: class Program { static void Main(string[] args) { var temp = args.AsEnumerable();

问题 There are two descriptions of the delegate: first, in a third-party assembly: public delegate void ClickMenuItem (object sender, EventArgs e) second, the standard: public delegate void EventHandler (object sender, EventArgs e); I'm trying to write a method that will receive a parameter of type EventHandler and will call third-party library, with the parameter ClickMenuItem. How to convert the ClickMenuItem to EventHandler? 回答1: Fortunately, it's simple. You can just write: ClickMenuItem

问题 I made a custom class that handles audio recording/playback and put a Protocol in that class. I implemented the Protocol in a UIViewController class and called my setDelegate method for my AudioHelper class. I am getting a compile error that has to do with my init() . Not exactly sure how to get rid of the error: use of 'self' in method call 'setupAudioSession' before super.init initializes self override init() { setupAudioSession() super.init() } How do I resolve this error? And why do I

问题 An event can contain many handlers which are defined using delegate , my current understanding is that delegate is just an abstraction of function pointer. Since an event , which associated with a delegate type, can add / remove many delegates into it, and composite pattern treats a composite object the same as the terminal object, so the idea is: composite.onTriggered(); // Internally: // foreach(handler in composite) // { // handler.onTriggered(); // } will in turn call every handlers

问题 An event can contain many handlers which are defined using delegate , my current understanding is that delegate is just an abstraction of function pointer. Since an event , which associated with a delegate type, can add / remove many delegates into it, and composite pattern treats a composite object the same as the terminal object, so the idea is: composite.onTriggered(); // Internally: // foreach(handler in composite) // { // handler.onTriggered(); // } will in turn call every handlers

问题 An event can contain many handlers which are defined using delegate , my current understanding is that delegate is just an abstraction of function pointer. Since an event , which associated with a delegate type, can add / remove many delegates into it, and composite pattern treats a composite object the same as the terminal object, so the idea is: composite.onTriggered(); // Internally: // foreach(handler in composite) // { // handler.onTriggered(); // } will in turn call every handlers

来源： https://stackoverflow.com/questions/24806194/difference-between-explicit-delegate-and-method-group-in-a-thread-constructor

来源： https://stackoverflow.com/questions/63765853/ansible-delegate-to-behaving-absurd-when-used-inside-a-loop

来源： https://stackoverflow.com/questions/64115223/utilizing-delegate-pattern-for-matrices