【C#】学习笔记(3) 关于Events使用的小Demo

关于Events事件的简单Demo.

目录结构：

Program.cs

 1 using System;
 2 namespace EventsDemo
 3 {
 4     class Program
 5     {
 6         static void Main(string[] args)
 7         {
 8             Book book = new Book();
 9             book.BookAdded += OnBookAdded;
10             book.AddBook("One");
11             book.BookAdded -= OnBookAdded;
12             book.AddBook("Two");
13             book.BookAdded += OnBookAdded;
14             book.AddBook("Three");
15             book.BookAdded -= OnBookAdded;
16             book.AddBook("Four");
17         }
18         static void OnBookAdded(object sender, EventArgs args)
19         {
20             System.Console.WriteLine("A book was added");
21         }
22     }
23 }

Book.cs

 1 using System;
 2 namespace EventsDemo
 3 {
 4     public delegate void BookAddedDelegate(object sender, EventArgs args);
 5     class Book
 6     {
 7         public void AddBook(string bookname)
 8         {
 9             if (BookAdded != null)
10             {
11                 BookAdded(this, new EventArgs());
12                 System.Console.WriteLine($"BookName:{bookname}");
13             }
14         }
15         public event BookAddedDelegate BookAdded;
16     }
17 }

输出：

 

posted @ 2019-08-12 22:35  BrainK_1400  阅读(315)  评论(0)  编辑  收藏  举报