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This article mainly explains "what is a C# generic delegate". Interested friends may wish to take a look at it. The method introduced in this paper is simple, fast and practical. Next, let the editor take you to learn "what is a C# generic delegate"?

Before learning about C # generic delegates, let's first take a look at what a C # delegate is, which is a type of reference method. Once a method is assigned to a delegate, the C# delegate will have exactly the same behavior as the method. The use of a delegate method can be the same as any other method, with parameters and return values, as shown in the following example: any method that matches the delegate's signature (consisting of return types and parameters) can be assigned to the delegate. This allows you to programmatically change method calls and insert new code into existing classes. As long as you know the delegate's signature, you can assign your own delegate method.

C # generic delegate code

Public delegate int PerformCalculation (int x, int y)

The ability to reference a method as a parameter makes a delegate an ideal choice for defining callback methods. For example, you can pass a reference to a method that compares two objects to a sorting algorithm. Separating the comparison code makes it possible to write algorithms in a more general way.

C # delegation has the following characteristics:

The ◆ C# delegate is similar to the C++ function pointer, but it is type safe.

◆ C# delegates allow methods to be passed as parameters.

◆ C# delegates can be used to define callback methods.

◆ C # delegates can be linked together; for example, multiple methods can be called on an event.

The ◆ method does not need to match the delegate signature exactly.

◆ C # 2.0 introduces the concept of anonymous methods, which allow code blocks to be passed as parameters instead of individually defined methods.

Understanding and application of C # generic delegation:

C # delegates can define their own type parameters. Code that references a generic delegate can specify type parameters to create a closed construction type, just like instantiating a generic class or calling a generic method, as shown in the following example:

C # generic delegate code

Public delegate void Del < T > (T item); public static void Notify (int I) {} Del < int > M1 = new Del < int > (Notify)

Version 2.0 of C # has a new feature called method group conversion, which applies to specific delegate types and generic delegate types, and allows you to write to the previous line using the following simplified syntax:

C # generic delegate code

Del < int > m2 = Notify

Delegates defined within a generic class can use generic class type parameters in the same way as class methods.

C # generic delegate code

Class Stack < T > {T [] items; int index; public delegate void StackDelegate (T [] items);}

The code that references the delegate must specify the type variable that contains the class, as follows:

C # generic delegate code

Private static void DoWork (float [] items) {} public static void TestStack () {Stack < float > s = new Stack < float > (); Stack < float > .StackDelegate d = DoWork;}

Generic delegates are particularly useful when defining events based on typical design patterns, because sender parameters can be strongly typed and no longer need to be cast to Object or reverse cast.

C # generic delegate code

Delegate void StackEventHandler < T, U > (T sender, U eventArgs); class Stack < T > {public class StackEventArgs: System.EventArgs {} public event StackEventHandler < Stack < T >, StackEventArgs > stackEvent; protected virtual void OnStackChanged (StackEventArgs a) {stackEvent (this, a) }} class SampleClass {public void HandleStackChange < T > (Stack < T > stack, Stack < T > .StackEventArgs args) {}} public static void Test () {Stack < double > s = new Stack < StackEventArgs > (); SampleClass o = new SampleClass (); s.stackEvent + = o.HandleStackChange;} at this point, I believe you have a better understanding of what a C# generic delegate is, so you might as well do it! Here is the website, more related content can enter the relevant channels to inquire, follow us, continue to learn!

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