When/Why 您会在常规事件上使用 EventHandler 吗？

Question

使用 EventHandler 和只定义事件在功能上有区别吗？

Answer 1

这是两个不同的东西

event 声明一个事件：

https://msdn.microsoft.com/en-us/library/8627sbea.aspx

EventHandler 定义事件将引发的方法：

https://msdn.microsoft.com/en-us/library/system.eventhandler(v=vs.110).aspx

EventHandler<TEventArgs> 是自定义 EventArgs:

的便捷包装器

https://msdn.microsoft.com/en-us/library/db0etb8x(v=vs.110).aspx

订阅事件的不同方式

using System;

namespace ConsoleApplication3
{
    internal class Program
    {
        private static void Main(string[] args)
        {
            // using a method
            MyEvent += Program_MyEvent;

            // using EventHandler, possible but not mandatory
            MyEvent += new EventHandler(Target);

            // using lambda syntax
            MyEvent += (sender, eventArgs) => { };

            // using delegate
            MyEvent += delegate (object sender, EventArgs eventArgs) { };

            // using delegate, signature is optional actually
            MyEvent += delegate { };
        }

        private static void Target(object sender, EventArgs eventArgs)
        {
        }

        private static void Program_MyEvent(object sender, EventArgs e)
        {
        }

        public static event EventHandler MyEvent;
    }

}

When/Why 您会在常规事件上使用 EventHandler 吗？

When/Why would you use a EventHandler over just a regular Event?

c#

events

event-handling

eventhandler