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The Impossibly Fast C++ Delegates, Fixed

by Sergey Alexandrovich Kryukov

Derived work based on the article by Sergey Ryazanov "The Impossibly Fast C++ Delegates": this good solution is fixed and further developed using C++11.

Asynchronous Multicast Delegates in Modern C++

by David Lafreniere

A C++17 standards compliant delegate library capable of targeting any callable function synchronously or asynchronously

Variadic Delegates

by Anton Chibisov

This tutorial showcases how to implement C++ delegates which are capable of being bound to methods and functions having arbitrary signature, i.e., any number and type of parameters and return value.

Monad like programming with C#

by Muraad Nofal

A haskell monad/(applicative)functor like interface in C# that extends IEnumerable.

Latest Articles

Asynchronous Multicast Delegates in C++

by David Lafreniere

A C++ standards compliant delegate library capable of targeting any callable function synchronously or asynchronously

Asynchronous Multicast Delegates in Modern C++

by David Lafreniere

A C++17 standards compliant delegate library capable of targeting any callable function synchronously or asynchronously

Extract and manipulate event handler delegates of Windows form controls

by yutaraa

Get, move, copy and delete event handler delegates of Windows form controls.

C++/CLI: Storing Lambda in a Delegate

by Jon McKee

How to do it and why it works

All Articles

Delegates

The Impossibly Fast C++ Delegates, Fixed

11 Mar 2017 by Sergey Alexandrovich Kryukov

Derived work based on the article by Sergey Ryazanov "The Impossibly Fast C++ Delegates": this good solution is fixed and further developed using C++11.

Asynchronous Multicast Delegates in Modern C++

19 Dec 2022 by David Lafreniere

A C++17 standards compliant delegate library capable of targeting any callable function synchronously or asynchronously

Variadic Delegates

13 Apr 2015 by Anton Chibisov

This tutorial showcases how to implement C++ delegates which are capable of being bound to methods and functions having arbitrary signature, i.e., any number and type of parameters and return value.

Monad like programming with C#

18 Sep 2013 by Muraad Nofal

A haskell monad/(applicative)functor like interface in C# that extends IEnumerable.

Learning C# (Day 11): Events in C# (A Practical Approach)

6 Jan 2017 by Akhil Mittal

This article of the series "Diving into OOP" will explain all about events in C#. The article focusses more on practical implementations and less on theory.

C# Expression Confusion

22 Aug 2013 by OriginalGriff

Neither the Expression or the params are datatypes: the former is similar to Func but returns a tree rather than a value (There is a good description here: http://stackoverflow.com/questions/793571/why-would-you-use-expressionfunct-rather-than-funct[^]).params is a C# keyword that lets you...

SystemFramework library

24 Nov 2011 by Scanix

SystemFramework defines interfaces, classes, and types to support a native runtime system with its own garbage collector, delegates, etc. The design of SystemFramework classes is similar to those of the .NET Framework.

Code is not working,pls have a look

28 May 2014 by OriginalGriff

Well no - they won't. You aren't calling them at all - you are just adding them to the list of methods to call when you do action the delegate. In fact, each time you press the button, you add four more methods to the list, so if you did call the delegate itself, after the first press it would...

Unable to understand multicast delegates

30 May 2014 by Raul Iloc

1. ExampleDelgate e3 = e1 + e2; create an delegate object e3 as sum of e1 and e2 this is similar with the adding into an "event" two methods, in this case the list will have the next 2 methods: Add and mul.So if you will invoke e3(20, 10); ==> both methods Add(20, 10) and mul(20,10) will be...

C# Like Event Handlers Pattern in Java

26 Mar 2017 by Danilow

Simulating C# event handlers in Java

why we use Delegates or when should we? what is the real need of it?

9 Dec 2011 by thatraja

Better check these threadswhen & why to use delegates?[^]Why do we need C# delegates[^]Advantages of using delegates?[^]Delegates, Why?[^]

why we use Delegates or when should we? what is the real need of it?

9 Dec 2011 by Uday P.Singh

already answered:What is delegate..? What is the use of it..?[^]hope it helps :)

Weird compiler behaviour...?

23 Dec 2012 by Mehdi Gholam

Posted from the comment:Check if the "optimize code" is set in your project.

Delegates with return type

30 May 2014 by Thomas Daniels

Change the return type of your delegate from void to int:public delegate int ExampleDelgate (int x, int y);Also, when you try to access the mul method with a delegate, you should pass 30 and 10 as parameters and not as a multiplication:ed = new ExampleDelgate(Democlass.mul);//ed(30...

Delegates with return type

30 May 2014 by Sergey Alexandrovich Kryukov

In addition to the correct Solution 1:You don't need a separate delegate type declaration for such a simple signature; it is already done for you and is System.Func. You don't need a separate type declaration at all:System.Func ed = new System.Func

Delegates name of method.

6 Jan 2015 by Matt T Heffron

If I understand your question, you've almost got it correct in your code above: class Program { static void Main(string[] args) { somedelegate process = new somedelegate(someclass.somemethod); // NOTE: no parens () process(4); } ...

Delegates name of method.

6 Jan 2015 by Sergey Alexandrovich Kryukov

Solution 1 is only good for static methods. Yes, you asked about static methods, but this is not the only possibility. But this is also possible with the class instance. Compare: delegate int SomeDelegate(int i); class Implementation { internal int SomeMethod(int i) { /*...

What is the need of delegate than calling the normal function via object of the class ?

2 Apr 2016 by OriginalGriff

Delegates are used for more than just "call this or that" - they can provide a "chain of methods to be called" for example. You use delegates already, quite a bit - you just don't realize it because they are "hidden" at the core of Event handling!One reason for a delegate based approach is...

Object reference not set to instance of object:weifenluo's dockpanel suite in C++/cli

3 Jul 2016 by OriginalGriff

This is one of the most common problems we get asked, and it's also the one we are least equipped to answer, but you are most equipped to answer yourself.Let me just explain what the error means: You have tried to use a variable, property, or a method return value but it contains null -...

Call method using reflection with better performance

18 Aug 2017 by Mehdi Gholam

First don't use reflection unless you need it and you know what you are doing, so if your method counts is low use a switch statement: switch(comm.Method) { case "method1" : this.Method1(comm.Data); break; ...// and so on } You can also use a Dictionary with...

Where delegate in C# can be used in project

2 Jun 2020 by Richard MacCutchan

You can use them everywhere in your project. See Delegates - C# Programming Guide | Microsoft Docs[^].

How do I convert a function taking a func[T] to be asynchronous?

26 Aug 2020 by Richard Deeming

The return type of an async function will need to be Task or ValueTask, so your delegate type will be either Func> or Func>. The function runner effectively doesn't care whether or not the function is async - it just...

C# what passes arguments to anonymous functions?

23 Mar 2018 by User 7407470

For every element in the List 'list' the .NET method 'FindAll' calls the delegate method to get a value (true or false) indicating whether the value should be added to the List 'evenNumbers'. So, the .NET method 'FindAll' passes the value i to the delegate method. ...

A AsyncCallback of a Delegate opens a non reponding form

19 Sep 2011 by Member 7835126

Hello!I'm trying to use a async Delegate to show and populate a form but the form show up and stays Not Responding.Normally the form opens OK when it's sync with the code.Example situation:Before Class:Public Delegate Sub MyAsyncDelegate()In primary sub:Dim del As...

C# Register Two Events, but only one reaction, please help me

2 Nov 2011 by HAOYE850815

Dear guys, I am currently working on a GPS tracking software. It should implement a function to trigger GPS data logging if GPS enter in a specific area and stop logging after going out of boundary.Anyway, My problem is if I select GPS as a observable object and make a GPSMonitor class...

C# Register Two Events, but only one reaction, please help me

2 Nov 2011 by Nish Nishant

Is this a typo?gpsmonitor.GeofenceOutPositioned += new GPSMonitor.PositionInGeofenceEventHandler(RaiseInEvent);gpsmonitor.GeofenceOutPositioned += new GPSMonitor.PositionInGeofenceEventHandler(RaiseOutEvent);If not, there's your bug.

why events in ASP controls are defined as delegates

19 Dec 2011 by Sergey Alexandrovich Kryukov

If looks like you have no idea how delegates work, not mentioning events and their relationship. It's hard to explain all in once, while C# and .NET manuals provides detailed explanation. First, read this: http://en.wikipedia.org/wiki/Delegation_%28programming%29[^].Start here:...

use of invoke method with assigned method

13 Apr 2012 by OriginalGriff

The easiest way is to set up a method for it: private void SetLabelText(Label l, string s) { if (InvokeRequired) { Invoke(new MethodInvoker(delegate { SetLabelText(l, s); })); } else ...

no overload for '' matches delegate 'system.eventhandler'

27 Aug 2012 by sinaavakh

Hello :)i want to create an array of object !i added my mywinsocket.ocx to my projectcheck this ! AxProject1.AxSocket[] Socket = new AxProject1.AxSocket[5];// load myclass private void button1_Click(object sender, EventArgs e) { for (int...

Raising an Event in user control

11 Aug 2013 by OriginalGriff

This Tip is intended to automate the process of adding them to your code: A Simple Code Snippet to Add an Event[^] but it provides the template for how to create and then signal an event from your user control. When you signal it to any subscribing handlers, all you do is call the "On

Raising an Event in user control

11 Aug 2013 by ridoy

You question is not clear enough to understand,but these will help you a lot..How to Create an Event for a User...

A Mimetic C# Style Multicast Event Implementation with C++

26 Aug 2013 by paladin_t

A Mimetic C# Style Multicast Event Implementation with C++

[Concept] Delegate,Lamda Expression c# windows form

30 Nov 2013 by Karthik_Mahalingam

Try these linkmight be useful for you.C# Delegates, Anonymous Methods, and Lambda Expressions – O My![^]this link contians basics of lambda very informative...

How Do I Cross-Threading Help

24 Apr 2014 by Sergey Alexandrovich Kryukov

There is no such concept as "invoke in class". This is irrelevant. It's important in what thread you are running some code. There are two very different cases: if you need to invoke some operation to a UI thread, or to do it in some custom thread. I answered both question in detail in my past...

Delegates with return type

30 May 2014 by CHill60

ProgramFOX has solved your problem, however you may also find this CodeProject article useful - C# - Delegates 101 - A Practical Example[^]

Anonymous Method in Delegates

2 Jun 2014 by CPallini

Here you are (see MSDN[^]) static void Main(string[] args) { Democlass d = new Democlass(); ExampleDelgate e1 = new ExampleDelgate(d.Add); ExampleDelgate e2 = delegate(int x, int y){ Console.WriteLine(x+y);}; // anonymous method e1(20, 10); e2(20,...

How to create an event in a c# wrapper for a c++ dll

3 Dec 2014 by mccaber82

Hi,I come from a .net background and I am fairly new to developing in C++. I am building a library which carry's out low level functionality, wrapped by a C# library so it can be used in other projects.I am well used to events in C# and raising events when something meaningful happens. ...

How to create an event in a c# wrapper for a c++ dll

5 Dec 2014 by KarstenK

I have added callback support to my article Calling all stations which handles now also callbacks from and into C++. Step through the code and see my solutions.

How do I rewrite a Command using explicit functions?

20 Jan 2016 by Richard Deeming

Seems simple enough:private bool MyCommandCanExecute(object state){ return true;}private void MyCommandExecute(object state){ // Do something...}...ICommand myCommand = new Command(MyCommandExecute, MyCommandCanExecute);

What is the type I need to store for this asynchronous function?

22 Mar 2016 by Patrick Skelton

Hi,I have a class which contains a function that needs to be called asynchronously at a later time. Similar to this:public class MyClass{ public Task SomeFunctionAsync() { // Do a long-running thing... }}I actually have a few of these classes, and I am...

Create a delegate from methodinfo (2)

23 Mar 2017 by Richard Deeming

Based on some crude testing, I suspect the problem is actually the other way round: you can create the delegate when the method hasn't been overridden, and you can't create the delegate when the method has been overridden.Class Foo Protected Overridable Sub Click() ...

Cannot convert lambda expression to type bool

11 Dec 2017 by phil.o

You can also do shorter: public static bool CheckisOdd(int s) { return ((s % 2) != 0); } or quicker: public static bool CheckisOdd(int s) { return ((s & 1) == 1); }

Trying to pass function from master to content page with delegate, issue finding contentcallevent in contentpage

23 Apr 2018 by F-ES Sitecore

You need to tell the content page what the specific type of the master page is before you can use any public properties\methods on that master page. This can be done using the MasterType derective Working with ASP.NET Master Pages Programmatically[^] Master page has this dropdown ...

Unsubscribing from an event still it's getting fired many times, how to stop it?

5 Jun 2018 by OriginalGriff

Please, look at your code! Why would you write this: SerialPort port = new SerialPort(); ... if (port.IsOpen) { port.Close(); port.Dispose(); } port.Open(); If it's a new port, it can't be...

Altering the way a function operates

7 Dec 2018 by Richard Deeming

Something like this would work: Func> factoredAreaOfCircle = factor => r => factor * Math.Pow(r, 2); Func> factoredDiameterOfCircle = factor => r => 2 * factor * r; Func iNeed = factoredDiameterOfCircle(3);...

Where delegate in C# can be used in project

2 Jun 2020 by OriginalGriff

To add to what Richard has said, your whole Windows app is based on delegates, though they are hidden "behind the scenes". Every time you setup, handle, or remove an event handler, that's implemented using delegates ... just you have some...

How to recieve response from server

26 Jul 2020 by Member 14686752

The client is in c# and the server is in C++. Client is as follows: client.cs namespace clinetspace { public class client { [DllImport("Server.dll")] static public extern void CallServer(IntPtr obj, int a); ...

DelegateCommand

How do I convert a function taking a func[T] to be asynchronous?

26 Aug 2020 by Patrick Skelton

I have a class that has a function that runs the supplied delegate, which is of type Func, as shown in the following code. public static class FunctionRunner { public static int RunSuppliedFunction( Func aFunctionReturningInt ) =>...

How do I convert a function taking a func[T] to be asynchronous?

26 Aug 2020 by Patrick Skelton

With the helpful nudge from @Richard Deeming, I have got the code compiling like this (which also moves a step closer to showing what the point of all this is): public static class FunctionRunner { public static async Task...

How do I get the number of event subscribers in the add and remove blocks?

14 Mar 2017 by User 7407470

How about this?private EventHandler _myEvent;private int _myEventSubscribersCount;public event EventHandler MyEvent{ add { _myEvent += value; _myEventSubscribersCount = _myEvent.GetInvocationList().Length; } remove { _myEvent -=...

How to convert .NET4 lambda addhandler , sub(arg) eventCompleted(arg1, arg2) to .NET2

13 Sep 2011 by TikElentrik

Hi,I have a small problem. I dont know how to convert a .net4 addhandler to .net2Can someone give me a example or a link?Or a definition of how it's named, so i can search google.The event signature don't equals the ASub signature. Dim name As String = "TikElentrik" ...

How to convert .NET4 lambda addhandler , sub(arg) eventCompleted(arg1, arg2) to .NET2

12 Sep 2011 by Richard MacCutchan

According to MSDN here[^] and here[^] the statement is the same in both versions. However, neither of them seem to match what you have coded.

How to convert .NET4 lambda addhandler , sub(arg) eventCompleted(arg1, arg2) to .NET2

12 Sep 2011 by Wayne Gaylard

There is no difference between .Net 4.0 and .Net 2.0 event handling in VB. You need to declare the method first, and ensure the event handler has the same signature as the event declaration.Try something like this:-Public Event someEvent(ByVal name As String, ByVal b As String) ...

How to convert .NET4 lambda addhandler , sub(arg) eventCompleted(arg1, arg2) to .NET2

13 Sep 2011 by TikElentrik

Thanks to the persons who tried to help me. I found a solution.Friend Class Solution Public Class SomeThing 'A bunch of stuff Public Name As String Public Sub New(ByVal Name As String) Me.Name = Name End Sub End Class Public...

why we use Delegates or when should we? what is the real need of it?

9 Dec 2011 by awaisdar

i have some ques.i have understood the concept of handling the event using delegates (as some extent not whole). but there is some thing else here.Asynchronous and Synchronous Methods.1.What is the difference between the two? simple example.2. i have a method that takes 30 mint to complete,...

Refactoring Hooking and Unhooking Events TIP

4 Jan 2012 by zenwalker1985

Refactoring Hooking and Unhooking Events TIP

Delegation Issues in VB.NET

5 Jan 2012 by Nara Har

Hello All,I have a form and I want to ensure that none of the input fields should be left blank and the txtUPrice should hold only numeric values.The below is the code that I devised.Initially when I checked for focus issues (Initial IF structure) it went fine. But when I...

Delegation Issues in VB.NET

6 Jan 2012 by Estys

Yes, your second "if" is messing things up.Try If x.Text = "" Then x.Focus() ErrPvdr.SetError(x, "Cannot be a blank input") ElseIf x.Name = "txtUprice" And (Not IsNumeric(x.Text)) Then x.Focus() ErrPvdr.SetError(x, "Cannot...

Impersonation and Delegate in WCF

26 Mar 2012 by Manjunathabe011

Hi All,I have a scenario where I need to do double hop authentication. I want to Impersonate the Users in WCF service layer but want to pass the same Windows credentials of Client to DAL. My DB needs windows authentication. How can I achieve this. Thanks,Manju

BackgroundWorker shows progress but main thread might need to show progress too

5 Apr 2012 by bobishkindaguy

SOLVED - PLEASE SEE COMMENTS BELOW IF YOU ARE INTERESTED IN HOW THIS WORKED OUT, SINCE IT IS A 2-PART SOLUTION, BOTH OF WHICH ARE POTENTIALLY USEFUL TO OTHERS.Often, users will go to my program's "import data" window to initiate an import of data from a file or spreadsheet to our database....

BackgroundWorker

use of invoke method with assigned method

13 Apr 2012 by Member 8404471

Hey everyone,I'm trying to send the value from a serial port via myPort.DataReceived() to a textlabel on my windows form. Error is of course, that I can't access the control from a different thread. I know i need to use invoke for that but can't get it right. I tried this:void...

Delegates and events.

4 Jul 2012 by ErickTreeTops

i'm trying to understand delegates and events and wrote a simple app based on an example.namespace DelegateTest{ public partial class Form1 : Form { BroadcastClass B = new BroadcastClass(); ListenToClass1 L1 = new ListenToClass1(); ...

Delegates and events.

4 Jul 2012 by Richard MacCutchan

I don't know where you found your example but Microsoft provide a very good one here[^].

no overload for '' matches delegate 'system.eventhandler'

27 Aug 2012 by Sangramsingh Pawar

Your problem is in below method private void Socket_DataIncome(object sender,AxProject1.__Socket_DataArrivalEvent e) { }This error occured due to passing wrong arguments.System.EventHandler contains below two arguments1)Object...

Referencing events in C# using interfaces - A simple approach

6 Sep 2012 by zaphoed

Passing event references as interfaces in C# by proxifying them within "EventReference" instances.

Weird compiler behaviour...?

23 Dec 2012 by Sander Rossel

So I'm having a very weird problem... I'm working on a project which does some Reflection stuff. One of the things it does is read the name of methods. I've got code that, in essence, looks like the following.Public Class Form1 Private Sub Form1_Load(sender As System.Object, e As...

c# using delegates to communicate between forms and networkcommunicator class

29 Dec 2012 by Cyberbird85

Hello everyone!I'm trying to develop an application in c# i currently have a code similar to the one attached below.Basically what it does is:Having multiple form, each of which would like to send message through the network, using my NetworkCommunicator class's SendMessage method.The...

c# using delegates to communicate between forms and networkcommunicator class

29 Dec 2012 by Christian Graus

You can't do anything OO over the network, because you have two different exes running. You can't use delegates between two exes on two machines.

Listening to all specified events of a from

14 Jun 2013 by Michelle Phoenix

Hello,I am building a form which has various controls on it, and each control has various methods that are handled, such as onLoad, Click etc. When certain methods are fired, I need to write a log entry that that specific control's _something method was fired.However, instead of adding...

Listening to all specified events of a from

14 Jun 2013 by Mehdi Gholam

Read the following :http://msdn.microsoft.com/en-us/library/ms228976.aspx[^]http://msdn.microsoft.com/en-us/library/system.reflection.eventinfo.addeventhandler.aspx[^]

Passing a function name as parameter to function

26 Jun 2013 by Tom Wauters

In ClassB public static void doStuffInB() { //do some really cool stuff. }in ClassA:private void Form1_Load(object sender, EventArgs e) { ClassB.doStuffInB(); }

Error on execution of a method (.NET / COM)

27 Jun 2013 by Jeneesh K. Velayudhan

I have one Initialize() in my class and I am calling a delegate wrapper method from this function as follows (the call back method will call around 20 times in a sec),public Initialize(){ CX_OUTPUT_CALLBACK cb = new CX_OUTPUT_CALLBACK(OutDelegateCb); ...

static-code-analysis

Passing a function name as parameter to function

26 Jun 2013 by MK-Gii

Hello Guys,I am having a hard time with passing a function name as a parameter to another function.I have the following setup:1. There are 2 classes (A and B)2. I am trying to write a function in class A which would be executing methods from class B.I know I can pass a class instance...

Passing a function name as parameter to function

26 Jun 2013 by Pheonyx

Hi,I do not know if this will help, but you could use reflection to execute a method off of a class.http://stackoverflow.com/questions/2202381/reflection-how-to-invoke-method-with-parameters[^]So if you instantiate an instance of class b then use reflection to find which ever method...

Raising an Event in user control

11 Aug 2013 by Star135

Can anyone help me out with the code or some good link ,i am not able to find proper code for practice for raising event in user control Thanks in Advance

Does anyone have a simple way of making this TreeView WinForm app multithreaded – the UI locks up.

18 Oct 2013 by OriginalGriff

Doing the Threading stuff is pretty easy - a Background worker will handle that: BackgroundWorker work = new BackgroundWorker(); work.DoWork += new DoWorkEventHandler(work_DoWork); work.ProgressChanged += new...

BackgroundWorker

use glutDisplayFunc(display) in my class

29 Oct 2013 by Mohammad Sharify

Hi allI use a class to write opengl program in C++,I want to use glutDisplayFunc(display)and this my display function:void graphic::dispaly(){ glClear(GL_COLOR_BUFFER_BIT); //call a function glutSwapBuffers();}Now ,I face this error:3 IntelliSense: argument of type...

use glutDisplayFunc(display) in my class

29 Oct 2013 by nv3

As Richard said, declare the display function in your graphic class as:class graphic{ ... static void display ();};and things should work.

Unable to Raise event from MasterPage

14 Nov 2013 by Imadoddin

Hi, I have a masterpage in which I have dropdown list, I want to handle SelectedIndexChanged Event of that dropdown list in cantent page.. So far I didMasterPage:Public Event SelectedIndexChange(ByVal sender As Object, ByVal e As System.EventArgs)Public Shared Sub...

Unable to Raise event from MasterPage

14 Nov 2013 by Jobless Creature

This Link may be of help...Save & Exit in Web Application[^]

pass an interop callback from C#, via C++ CLI, to native C++

29 Dec 2013 by Sergey Alexandrovich Kryukov

Yes, this is quite possible; and this possibility is quit often used, because big number of, for example, raw Windows API functions works through such callbacks.In this approach, a callback signature is represented by a .NET delegate type, and the actual function parameter passed to the...

pass an interop callback from C#, via C++ CLI, to native C++

30 Dec 2013 by Daniel Brousser

solved by using interfaces, thanks

Events and Delegates in Standard C++

10 Jan 2014 by Slavisa

Events and Delegates in Standard C++ implemented using Macro functions

Changing Button Property not reflecting in UI during Runtime in Windows Form Application C#

27 Mar 2014 by Divakar Raj M

I am trying to interactively change button properties in the UI visually. I have a sole button in my Windows Forms application and this is my code for the button clickprivate void button1_Click(object sender, EventArgs e) { button1.BackColor = Color.Red; ...

I Have 2Dropdownlist Controls In Usercontrols And If I Selected Dropdownvalues Iwant To Show That Values In Aspx Textbox Controls

27 May 2014 by Member 10755393

hi this vijayi have 2dropdownlist controls in usercontrols and if i selected dropdownvalues iwant to show that values in aspx textbox controls using delegates and events,iwant clear code iam new for .net

I Have 2Dropdownlist Controls In Usercontrols And If I Selected Dropdownvalues Iwant To Show That Values In Aspx Textbox Controls

27 May 2014 by Naz_Firdouse

check thisUser control with DropDownList adding OnSelectedIndexChanged

I Have 2Dropdownlist Controls In Usercontrols And If I Selected Dropdownvalues Iwant To Show That Values In Aspx Textbox Controls

27 May 2014 by R-a-v-i-k-u-m-a-r

Try thisprotected void GetMySelection(object sender, SelectedIndexChangedEventArgs e){ TextBox1.Text= e.SelectedItem.Text;}

Code is not working,pls have a look

28 May 2014 by Rakesh Agarwal1984

public partial class _Default : System.Web.UI.Page { public delegate void mydelegate(); public event mydelegate myevent; protected void Page_Load(object sender, EventArgs e) { } protected void Button1_Click(object sender, EventArgs...

Delegates with return type

30 May 2014 by ShaHam11

Hi I have two methods with return type one being instance and the other one is static method. I am trying to access those methods with delegates but i am unable to access it i get a error " Has wrong return typeusing System;using System.Collections.Generic;using System.Linq;using...

Anonymous Method in Delegates

2 Jun 2014 by OriginalGriff

We do not do your homework: it is set for a reason. It is there so that you think about what you have been told, and try to understand it. It is also there so that your tutor can identify areas where you are weak, and focus more attention on remedial action.Try it yourself, you may find it...

how to get a result from MVC controller with delegate using ajax

24 Jul 2014 by Marisco

I'm having a tough time getting the result from my controller, it has a function that contains a delegate funciont passint as a parameter.so the result is awais empty and then goes back after its finished.HTLMName:

Native C++ communicate with C#

17 Nov 2014 by ravijmca

Basically my code is looks like below Managed.dllManaged.csclass MyManagedClass{public ShowMessage(){System.out.println("My Message");}}Wrapper.dllref class Wrapper{};Native.libclass NativeClass{public:void NativeMessage(){cout

Native C++ communicate with C#

17 Nov 2014 by KarstenK

It is an easy task. Look at this code from Microsoft.You could ofcourse use your dll and function.

How to create an event in a c# wrapper for a c++ dll

4 Dec 2014 by barneyman

the easiest approach would be to write a COM object in the DLL - create an ATL simple object with a methods (say) HRESULT Register(IUnknown *eventCallback), HRESULT UnRegister(void)(don't bother with dual/dispatch, custom is fine, but make it automation safe)Use tlbimp (on the generated)...

Delegates name of method.

6 Jan 2015 by Inimicos

using System;using System.Collections.Generic;using System.Linq;using System.Text;using System.Threading.Tasks;namespace delegateexample{ delegate int somedelegate(int i); class someclass { public static int somemethod(int i) { return i...

How can I push notification feature for my web application ( a small online store). I really am very confused

11 Nov 2015 by uddyorizu

may be signalR could help you here.As am not sure if you mean the mobile app push notifications, do forgive if its not what you need.see http://www.asp.net/signalr[^]

Firing events in loop are not updating UI in sequence

29 Nov 2015 by sunil kumar meena

I was trying to update status on UI for a Long Running Operating. I've created a demo form based application, task it have multiple rows, each row is having days and default values in each column of datagrid is 0, once computation file computes one iteration for one day it will update UI and set...

multi-threading

Firing events in loop are not updating UI in sequence

29 Nov 2015 by George Jonsson

I think the problem is that you when you pass the event argument, you don't pass it is a value but as a reference. See Parameter passing in C#[^]As you only create one instance of MessageEventArgs me = new MessageEventArgs();, you only have one place in the memory where your data is...

multi-threading

How do I rewrite a Command using explicit functions?

19 Jan 2016 by Patrick Skelton

Hi,I am trying to get my head around ICommand. I've done a lot of reading. Almost all of it shows the mechanics of the Command being specified using lambda syntax. I can see the value of that, but, simply to deepen my understanding, I would like to know how to write the code long-hand,...

What is the need of delegate than calling the normal function via object of the class ?

2 Apr 2016 by Sergey Alexandrovich Kryukov

Your logic is badly, badly flawed. You start from the point where there should not be any essential difference by definition, and then, based on that, draw a conclusion that there is no difference.If you still did not get it, I'll explained on another example. This is like considering a...