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This article will explain in detail the example analysis of the nature of the C# event. The editor thinks it is very practical, so I share it for you as a reference. I hope you can get something after reading this article.

C # events are essentially wrappers of messages and are useful tools provided by the IDE programming environment to simplify programming. This encapsulation is implemented during the form process. Each IDE encapsulates many Windows messages, such as:

Event

Message

OnActivate

WM_ACTIVATE

OnClick

WM_XBUTT

ONDOWNOnCreate

WM_CREATE

OnDblClick

WM_XBUTT

ONDBLCLICKOnKeyDown

WM_KEYDOWN

OnKeyPress

WM_CHAR

OnKeyUp

WIN_KEYUP

OnPaint

WM_PAINT

OnResize

WM_SIZE

OnTimer

WM_TIMER

With this in mind, we complete the C# event that can encapsulate ourselves. Through the above introduction, I believe you already have a certain understanding of the Windows message mechanism. Through Windows message programming, we can achieve not only many general functions, but also many functions that are not provided by IDE class libraries; in addition, we can also intercept messages through message hooks and change their default processing functions, thus breaking through the limitations of platform or software functions and greatly extending the functions of programs; we can also modify the default form process to respond to messages according to our own requirements Or customize messages, implement instant messaging between programs, and so on. Through more in-depth study, we will also come into contact with more Windows message mechanism related to other Windows relatively low-level knowledge, if you can do so, suddenly look back, you will find that you are not far from the "master".

The form procedure is actually a callback function. The so-called callback function is actually a function called by the Windows operating system or external programs. Callback functions generally have a specified parameter format and are passed to the caller by address. The window is called by the Windows operating system, and when a window is created, the callback function address is passed in when the form handle is allocated. So why can't we program to see this callback function? This is because our programming tools have generated a default form procedure for us, and what this process needs to do is to determine different message types and then do different processing. For example, you can generate C# events for keyboard or mouse input.

This is the end of the article on "sample Analysis of the Nature of C# events". I hope the above content can be helpful to you, 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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