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This article will explain in detail the timing of the use of C#asynchronous delegation. Xiaobian thinks it is quite practical, so share it with you as a reference. I hope you can gain something after reading this article.

In my impression, delegation often appears on three occasions (maybe more, my level is limited).

C#asynchronous delegate delegate the use of timing 1, event calls (most commonly used).

C#asynchronous delegate the use of the time 2, thread call.

C#asynchronous delegate the time to use 3, synchronous asynchronous call.

Event invocation (the most common) is where delegates are used the most. We often use forms to define events so that data can be passed between windows. The most common situation is that in order to query a customer, the user clicks the "Query" button in Form B to pop up a customer query form (defined as A here). After querying the specified result in A, click the "Select" button to close A. The customer information queried is obtained on Form B. In this case, we typically define an event in A and then write a method (function) in B that is called when the event occurs. So how to combine the events of A and the methods of B? At this time, you need to use delegation. In effect, delegates are the bridge between events and methods. If you don't understand, look at the file class.designer.cs, when we select the click button event on the button, it automatically creates an associated delegate and event function, for example.

this.btnStart.Click += new System.EventHandler(this.btnStart_Click);

Delegates are also required for thread invocation. Why is that? Consider that threads primarily express the "execution facts" of program code in modules (MFC in simple terms). So the thread to call the function code, how to call the function? With that said, we know that delegates (i.e. function pointers) are bridges between functions and other things (events, threads). Therefore, when the thread is called, it is also necessary to use a delegate to connect the function to be executed through the delegate. For example:

C#Asynchronous delegate example application:

class Test { static void Main() { Thread newThread = new Thread(new ThreadStart(Work.DoWork)); newThread.Start(); } } class Work { Work() {} public static void DoWork() {} }

The "new Thread(new ThreadStart(Work.DoWork));" part of the above code is the delegated part. ThreadStart delegate, which represents the method to call when this thread begins execution. Therefore, a delegate is required at thread invocation time.

About "C#asynchronous delegate what are the timing of the use of" this article is shared here, I hope the above content can be of some help to everyone, so that you can learn more knowledge, if you think the article is good, please share it for more people to see.

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