事件，在事件引发时添加方法 [英] Events, add a method when event raised

问题描述

public delegate void myDelecate();
class A
    {
        public event myDelecate myEvent;
    public void everaise()
        {
        if(myEvent!=null)
                myEvent();
        }
     }
class Program
    {
        static void Main(string[] args)
        {
        A obj = new A();
            obj.myEvent += new myDelecate(DEF);
            obj.everaise();
    Console.ReadLine();
        }

        public static void DEF()
        {
            Console.WriteLine("DEF method called");
        }
}

如何将这些代码变成一行代码，

obj.myEvent + = new myDelecate（DEF）;

obj.everaise（）;

how to make these codes into a single line of code,
obj.myEvent += new myDelecate(DEF);
obj.everaise();

推荐答案

你可以自定义添加/删除活动的处理程序：

You can have custom add/remove handlers for an event:

class A
{
    private myDelecate del;
    public event myDelecate myEvent
    {
        add
        {
            del += value; // add handler
            value(); // call the method being added
            //del(); // call all the methods added so far
        }
        remove
        {
            del -= value;
        }
    }
}

您无需调用公共方法来举起活动：

And you don't need to call the public method to raise the event:

void Main()
{
    A obj = new A();
    obj.myEvent += new myDelecate(DEF);
    //obj.everaise();
}

请注意，这只会调用添加的代理。您的原始解决方案调用了添加到事件中的所有代理。

Please note that this will only invoke the delegate being added. Your original solution invoked all the delegates that were added to the event.

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